Out-of-Bounds Write in GNU C Library TSIG Print Functions

Publication date: 2026-04-28

Last updated on: 2026-05-05

Assigner: GNU C Library

Description

The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.

CVSS Scores

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Meta Information

Published

2026-04-28

Last Modified

2026-05-05

Generated

2026-07-06

AI Q&A

2026-04-28

EPSS Evaluated

2026-07-05

NVD

CVE-2026-5435

EUVD

EUVD-2026-26036

Affected Vendors & Products

Vendor	Product	Version / Range
gnu	glibc	From 2.2 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-787	The product writes data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

Executive Summary

This vulnerability involves deprecated functions in the GNU C Library (version 2.2 and newer) named ns_printrrf, ns_printrr, and fp_nquery. These functions fail to enforce the length of the buffer provided by the caller, which can lead to an out-of-bounds write when printing TSIG records.

Impact Analysis

The vulnerability can cause an out-of-bounds write, which may lead to memory corruption. This can potentially be exploited to cause application crashes, data corruption, or even arbitrary code execution depending on the context in which these functions are used.

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