Medium 4.8Published May 28, 2026

CVE-2026-42250Off-by-One Leading to Out-of-Bounds Write in bzip2

Updated under an hour ago (Oct 27, 2026, 10:23 PM ET)

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It affects bzip2. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for bzip2

Exploited in the last 30 days

bzip2 contains an off‑by‑one error in the bzip2recover utility. When processing a specially crafted file, the application performs an out‑of‑bounds write to a global buffer, resulting in memory corruption and a crash (denial of service). This issue was fixed in bzip2 patch 35d122a3df8b0cc4082a4d89fdc6ee99f375fe67

CVSS: 4.8 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Weakness (CWE): CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: CERT-PL
NVD analysis: Awaiting Analysis
Record last updated: Jun 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

bzip2 bzip2 bzip2:bzip2 (from the name)	through 1.0.8; 35d122a3df8b0cc4082a4d89fdc6ee99f375fe67 not affected	CNA record

References

References

https://cert.pl/en/posts/2026/05/CVE-2026-42250/	third-party-advisory
https://sourceware.org/bzip2/	product
https://inbox.sourceware.org/bzip2-devel/20260528145407.293768-1-mark@klomp.org/	vendor-advisory
https://sourceware.org/cgit/bzip2/commit/?id=35d122a3df8b0cc4082a4d89fdc6ee99f375fe67	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.