CVE-2026-5435 Potential buffer overflow in ns_sprintrrf TSIG handling path
Out-of-bounds write in glibc TSIG handling allows attackers to execute arbitrary code or cause denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-5435?
CVE-2026-5435 is a high-severity memory corruption vulnerability in Gnu Glibc, published on 28 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-787
Which versions are affected by CVE-2026-5435?
It affects 1 product.
Products include Gnu Glibc.
How do I fix CVE-2026-5435?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-5435 being exploited?
There is no known exploitation of CVE-2026-5435 in the wild and no public exploit code.
Other vulnerabilities in Gnu Glibc
Sources
Also known as AZL-84599, BELL-CVE-2026-5435, DEBIAN-CVE-2026-5435, ECHO-53d2-a97b-142d, GHSA-32rw-r8mp-pw42, MINI-2w45-2j8f-x4g4 and 6 more.