- Issued:
- 2026-05-26
- Updated:
- 2026-05-26
RHSA-2026:20565 - Security Advisory
Synopsis
Important: squid:4 security update
Type/Severity
Security Advisory: Important
Red Hat Lightspeed patch analysis
Identify and remediate systems affected by this advisory.
Topic
An update for the squid:4 module is now available for Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions, and Red Hat Enterprise Linux 8.6 Telecommunications Update Service.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
Squid is a high-performance proxy caching server for web clients, supporting FTP, and HTTP data objects.
Security Fix(es):
- squid: Squid: Denial of Service via heap Use-After-Free vulnerability in ICP handling (CVE-2026-33526)
- Squid: Squid: Denial of Service via crafted ICP traffic (CVE-2026-32748)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Solution
For details on how to apply this update, which includes the changes described in this advisory, refer to:
Affected Products
- Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life 8.6 x86_64
- Red Hat Enterprise Linux Server - AUS 8.6 x86_64
- Red Hat Enterprise Linux Server - TUS 8.6 x86_64
- Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.6 ppc64le
- Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6 x86_64
- Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle Long Life 8.6 aarch64
- Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle Long Life 8.6 ppc64le
- Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle Long Life 8.6 s390x
Fixes
- BZ - 2451574 - CVE-2026-33526 squid: Squid: Denial of Service via heap Use-After-Free vulnerability in ICP handling
- BZ - 2451577 - CVE-2026-32748 Squid: Squid: Denial of Service via crafted ICP traffic
Note:
More recent versions of these packages may be available.
Click a package name for more details.
Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| x86_64 | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: d9d61e2135b220b3d61ae42ef3168afe872f28e6ba90ec1e7c12f99ee0cd09bf |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: fcf34d948d19d8ceec11c33bfbd410918882c1e2d5f98d317d47f40935a8beca |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 3a323f9bd1ce4c4fdba3eed2f8c5ab67ef86553708394d3ef6c55c579d339c60 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 1b13a8613f81f5551073df17797db405c70acc0e332bbc915d50459e2e7f4530 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: b037f2838d83670bc84d104ccb9fd30a0ea17ce9ba739ff58b1dd96763bb82ba |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: 1240250827034d448006bf0cb9de62282d78274f8bd9eba6122f81f873f55083 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: ebb82db21e7b9dd78f7c773f4c42e91cfed2877bc41fa1d3c5efbe247dd50d3d |
Red Hat Enterprise Linux Server - AUS 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| x86_64 | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: d9d61e2135b220b3d61ae42ef3168afe872f28e6ba90ec1e7c12f99ee0cd09bf |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: fcf34d948d19d8ceec11c33bfbd410918882c1e2d5f98d317d47f40935a8beca |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 3a323f9bd1ce4c4fdba3eed2f8c5ab67ef86553708394d3ef6c55c579d339c60 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 1b13a8613f81f5551073df17797db405c70acc0e332bbc915d50459e2e7f4530 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: b037f2838d83670bc84d104ccb9fd30a0ea17ce9ba739ff58b1dd96763bb82ba |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: 1240250827034d448006bf0cb9de62282d78274f8bd9eba6122f81f873f55083 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: ebb82db21e7b9dd78f7c773f4c42e91cfed2877bc41fa1d3c5efbe247dd50d3d |
Red Hat Enterprise Linux Server - TUS 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| x86_64 | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: d9d61e2135b220b3d61ae42ef3168afe872f28e6ba90ec1e7c12f99ee0cd09bf |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: fcf34d948d19d8ceec11c33bfbd410918882c1e2d5f98d317d47f40935a8beca |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 3a323f9bd1ce4c4fdba3eed2f8c5ab67ef86553708394d3ef6c55c579d339c60 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 1b13a8613f81f5551073df17797db405c70acc0e332bbc915d50459e2e7f4530 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: b037f2838d83670bc84d104ccb9fd30a0ea17ce9ba739ff58b1dd96763bb82ba |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: 1240250827034d448006bf0cb9de62282d78274f8bd9eba6122f81f873f55083 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: ebb82db21e7b9dd78f7c773f4c42e91cfed2877bc41fa1d3c5efbe247dd50d3d |
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| ppc64le | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 1ba6e6a7a7f64c91b5f49112a2d3437e5a4156c04cb2664d9f06985ffd631fac |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 2ef0dadb839911f6fb556005df57f2531f2dd215e8bd7dceb39370910050c6a4 |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 1cd7655a19f36b9eaf1cc95fd3e85d2f3cfa1a76e9206ca639fb16f14634f3dd |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 2d8756169558e12e281f18a9da93cc49c525ef908c8f2533f81e3a98b22d1e68 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: 8ee707ffe64d5ee73506fed5ea9d1975dd7c519b21ceaa426dd8ec976a516f3f |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: f028b6488799774ac71928df8e5d05a7914a272dd11a0797eec5eae1e0bfa2dc |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: 621cff9fe9f7df0d6921fcf2aa6e8f433550852d41f450a01c5c83fa55bb4995 |
Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| x86_64 | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: d9d61e2135b220b3d61ae42ef3168afe872f28e6ba90ec1e7c12f99ee0cd09bf |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: fcf34d948d19d8ceec11c33bfbd410918882c1e2d5f98d317d47f40935a8beca |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 3a323f9bd1ce4c4fdba3eed2f8c5ab67ef86553708394d3ef6c55c579d339c60 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64.rpm | SHA-256: 1b13a8613f81f5551073df17797db405c70acc0e332bbc915d50459e2e7f4530 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: b037f2838d83670bc84d104ccb9fd30a0ea17ce9ba739ff58b1dd96763bb82ba |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: 1240250827034d448006bf0cb9de62282d78274f8bd9eba6122f81f873f55083 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.x86_64.rpm | SHA-256: ebb82db21e7b9dd78f7c773f4c42e91cfed2877bc41fa1d3c5efbe247dd50d3d |
Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle Long Life 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| aarch64 | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64.rpm | SHA-256: 31c61fd165ea82f7e30b0b4f8e9f9fd6a5eae832149c81c14fd706f902fed84a |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64.rpm | SHA-256: 450f2a9aa696793f5c1ffb9e62a89bb182e442404b5915306060cd696dbc71e2 |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64.rpm | SHA-256: 835ebb3c576f9b1c5ece2e8b3a5a44c0a87f57b3df4fe793c8d7984953397d63 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64.rpm | SHA-256: 3313cc4f037084e4f913b10b252a7750d6a5a282930643ad92982e3d1330893a |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.aarch64.rpm | SHA-256: 256eb678f2565a354d319bd8aff5fbfe8f702168d818e2f77d6b93d4ecbe969e |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.aarch64.rpm | SHA-256: 782d677bc97735d9dc80fb9c29943dbe118b2307d107155e54997f20458cfa22 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.aarch64.rpm | SHA-256: cec9a7dabb3bde8e51692bcc9a443626389d7cd314e7e06704b6425638db10a0 |
Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle Long Life 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| ppc64le | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 1ba6e6a7a7f64c91b5f49112a2d3437e5a4156c04cb2664d9f06985ffd631fac |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 2ef0dadb839911f6fb556005df57f2531f2dd215e8bd7dceb39370910050c6a4 |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 1cd7655a19f36b9eaf1cc95fd3e85d2f3cfa1a76e9206ca639fb16f14634f3dd |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le.rpm | SHA-256: 2d8756169558e12e281f18a9da93cc49c525ef908c8f2533f81e3a98b22d1e68 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: 8ee707ffe64d5ee73506fed5ea9d1975dd7c519b21ceaa426dd8ec976a516f3f |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: f028b6488799774ac71928df8e5d05a7914a272dd11a0797eec5eae1e0bfa2dc |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.ppc64le.rpm | SHA-256: 621cff9fe9f7df0d6921fcf2aa6e8f433550852d41f450a01c5c83fa55bb4995 |
Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle Long Life 8.6
| SRPM | |
|---|---|
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src.rpm | SHA-256: 2f43b6316609e9a09ecea6e01089d7d886d0024c1eae28f1c31d87670992f7ff |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.src.rpm | SHA-256: 38678265592fdaa148cc4930137467e98db3a78fd82b7a3cfa0c2f5176738a2e |
| s390x | |
| libecap-1.0.1-2.module+el8.1.0+4044+36416a77.s390x.rpm | SHA-256: 11155457578ba82d131c38520ef1e704de6c8b532b17ccfcdb0feb647158d7d5 |
| libecap-debuginfo-1.0.1-2.module+el8.1.0+4044+36416a77.s390x.rpm | SHA-256: c9809c43b34e764d8904dc2b31a213fe0dc49208feabcacd8106caef9d24b507 |
| libecap-debugsource-1.0.1-2.module+el8.1.0+4044+36416a77.s390x.rpm | SHA-256: 4c5372dcfd4429ace80a62242882c6dfbf39a9eef2c8b84c2aa2b7292b24ce68 |
| libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.s390x.rpm | SHA-256: 7c3257862efc0e7f5a93f35535fb2292ca7a11342ff72e3f03d5a934a86821f3 |
| squid-4.15-3.module+el8.6.0+24307+cba8e5bb.9.s390x.rpm | SHA-256: 2016bee48b618d2a89a44f91c580dccbea9e773bf6536cc89d3babf433155f3a |
| squid-debuginfo-4.15-3.module+el8.6.0+24307+cba8e5bb.9.s390x.rpm | SHA-256: 70c9af54e57b0ba23c8b7889780a398a1b9b14dff8275fd82aed36f5629e1441 |
| squid-debugsource-4.15-3.module+el8.6.0+24307+cba8e5bb.9.s390x.rpm | SHA-256: 888a32ae3ff45ccf17fc7e1783606b30058d201d53e2654bb00b493eec52d63c |
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