CVE-2026-9669
What it is
bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer. This could crash the process when processing untrusted data.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-121
- Record status
- Awaiting Analysis
Attack profile CVSS 4.0 · 8.2
- Attack vector
- Network
- Complexity
- High
- Attack requirements
- Present
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Fix and advisories
- https://github.com/python/cpython/commit/157a5df8cb5d82b33f918a7489e72ce95ceb12b6
- https://github.com/python/cpython/commit/1ba6135eae75ad8413413caeeedb56ae72320636
- https://github.com/python/cpython/commit/5755d0f083949ff3c5bf3a37e673e24e306b036e
- https://github.com/python/cpython/commit/619a12b2e545391dc436b3af79dda22337382a6f
- https://github.com/python/cpython/commit/938ec030e90c5e53f1faac6fab1643f14e4f4a79
- https://github.com/python/cpython/commit/991e6cf86496718c4ef00b362d640e00cb5c85b2
- https://github.com/python/cpython/commit/d3ca26983dfbccdf609f24ff5877dc3118e4702d
- https://github.com/python/cpython/pull/150600
References
- https://github.com/python/cpython/commit/157a5df8cb5d82b33f918a7489e72ce95ceb12b6
- https://github.com/python/cpython/commit/1ba6135eae75ad8413413caeeedb56ae72320636
- https://github.com/python/cpython/commit/5755d0f083949ff3c5bf3a37e673e24e306b036e
- https://github.com/python/cpython/commit/619a12b2e545391dc436b3af79dda22337382a6f
- https://github.com/python/cpython/commit/938ec030e90c5e53f1faac6fab1643f14e4f4a79
- https://github.com/python/cpython/commit/991e6cf86496718c4ef00b362d640e00cb5c85b2
- https://github.com/python/cpython/commit/d3ca26983dfbccdf609f24ff5877dc3118e4702d
- https://github.com/python/cpython/issues/150599
- https://github.com/python/cpython/pull/150600
- https://mail.python.org/archives/list/[email protected]/thread/DBJZETMGUIFK7DVUWMOXHD3Z6IX2QPSX/
- http://www.openwall.com/lists/oss-security/2026/06/08/17