CVE-2025-21671 (GCVE-0-2025-21671)
Vulnerability from cvelistv5 – Published: 2025-01-31 11:25 – Updated: 2026-05-11 21:04
VLAI
EPSS
VEX
Title
zram: fix potential UAF of zram table
Summary
In the Linux kernel, the following vulnerability has been resolved:
zram: fix potential UAF of zram table
If zram_meta_alloc failed early, it frees allocated zram->table without
setting it NULL. Which will potentially cause zram_meta_free to access
the table if user reset an failed and uninitialized device.
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-02-10 17:11 UTC
CWE
- CWE-416 - Use After Free
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
ac3b5366b9b7c9d97b606532ceab43d2329a22f3 , < fe3de867f94819ba0f28e035c0b0182150147d95
(git)
Affected: 0b5b0b65561b34e6e360de317e4bcd031bfabf42 , < 571d3f6045cd3a6d9f6aec33b678f3ffe97582ef (git) Affected: 6fb92e9a52e3feae309a213950f21dfcd1eb0b40 , < 902ef8f16d5ca77edc77c30656be54186c1e99b7 (git) Affected: 74363ec674cb172d8856de25776c8f3103f05e2f , < 212fe1c0df4a150fb6298db2cfff267ceaba5402 (git) |
guessed | |
| Linux | Linux |
Affected:
6.1.122 , < 6.1.127
(semver)
Affected: 6.6.68 , < 6.6.74 (semver) Affected: 6.12.7 , < 6.12.11 (semver) |
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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