CVE-2026-11972
CVE-2026-11972 — tarfile opened in streaming mode mishandles EOF
When using the "tarfile" module with a file opened in "streaming mode" (mode="r|") the tarfile module did not properly handle EOF, making archive parsing take exponentially longer.
Published Updated Sources: cvelistV5, PSF
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
1%
chance of exploitation in 30 days
CVSS base
8.2
HIGH
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 8.2 | CVSS 4.0 | HIGH | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-252
- CWE-606
- CWE-770
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1498.001Network Denial of Service: Direct Network Flood
- T1499Endpoint Denial of Service
- T1499.003Endpoint Denial of Service: Application Exhaustion Flood
References
10 on the record
- github.com/python/cpython/issues/151981
issue-tracking
- github.com/python/cpython/pull/151982
patch
- mail.python.org/archives/list/[email protected]/thread/AXPSKKTSRKXTTJULW3XSIC74WZNAAPPB/
vendor-advisory
- github.com/python/cpython/commit/3f031d431f80668e14f3bc066bbf4369cd9281b9
patch
- github.com/python/cpython/commit/4ce6bf7c8aa7725828a38981c306f214c1f29365
patch
- github.com/python/cpython/commit/7f0dc59c9a70f8f3b4da33d7c4a2ba552a7acc21
patch
- github.com/python/cpython/commit/e86666c9dd256d52d0fbef6feb1ea4a51768fdec
patch
- github.com/python/cpython/commit/eb63c0f94dfcbea7fda8eab6213818e134d67192
patch
Elsewhere on this site
- python software foundationevery CVE for this vendor
- CWE-252other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.