CVE-2015-7547

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Last Modified: UTC

Description

A stack-based buffer overflow was found in the way the libresolv library performed dual A/AAAA DNS queries. A remote attacker could create a specially crafted DNS response which could cause libresolv to crash or, potentially, execute code with the permissions of the user running the library. Note: this issue is only exposed when libresolv is called from the nss_dns NSS service module.

A stack-based buffer overflow was found in the way the libresolv library performed dual A/AAAA DNS queries. A remote attacker could create a specially crafted DNS response which could cause libresolv to crash or, potentially, execute code with the permissions of the user running the library. Note: this issue is only exposed when libresolv is called from the nss_dns NSS service module.

Statement

After updating the glibc package on affected systems, it is strongly recommended to reboot the system or restart all the affected services. For more information please refer to: https://access.redhat.com/articles/2161461

After updating the glibc package on affected systems, it is strongly recommended to reboot the system or restart all the affected services. For more information please refer to: https://access.redhat.com/articles/2161461

Additional information

  • Bugzilla 1293532: glibc: getaddrinfo stack-based buffer overflow
  • CWE-121: Stack-based Buffer Overflow
  • FAQ: Frequently asked questions about CVE-2015-7547

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v2 Score Breakdown
Red HatNVD

CVSS v2 Base Score

6.8

6.8

Attack Vector

Network

Network

Access Complexity

Medium

Medium

Authentication

None

None

Confidentiality Impact

Partial

Partial

Integrity Impact

Partial

Partial

Availability Impact

Partial

Partial

CVSS v2 Vector

Red Hat: AV:N/AC:M/Au:N/C:P/I:P/A:P

NVD: AV:N/AC:M/Au:N/C:P/I:P/A:P

Understanding the Weakness (CWE)

CWE-121

Availability

Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Acknowledgements

This issue was discovered by Google Security Team and Red Hat.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?

What can I do if my product is listed as "Will not fix"?

What can I do if my product is listed as "Fix deferred"?

What is a mitigation?

I have a Red Hat product but it is not in the above list, is it affected?

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

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