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CVE-2021-33909
fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an…
High7.8EPSS 9.8%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 9.8% · top 4.4% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Weakness
Affected products
n/a
- affected n/a
References (20)
- [debian-lts-announce] 20210720 [SECURITY] [DLA 2713-2] linux security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [debian-lts-announce] 20210720 [SECURITY] [DLA 2713-1] linux security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [debian-lts-announce] 20210720 [SECURITY] [DLA 2714-1] linux-4.19 security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- DSA-4941 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- FEDORA-2021-07dc0b3eb1 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- [oss-security] 20210722 Re: CVE-2021-33909: size_t-to-int vulnerability in Linux's filesystem layer (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20210825 Re: CVE-2021-33909: size_t-to-int vulnerability in Linux's filesystem layer (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20210916 Containers-optimized OS (COS) membership in the linux-distros list (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20210917 Re: Containers-optimized OS (COS) membership in the linux-distros list (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20210920 Re: Containers-optimized OS (COS) membership in the linux-distros list (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- https://www.oracle.com/security-alerts/cpujan2022.html (opens in a new tab)x_refsource_MISCx_transferred
- https://www.openwall.com/lists/oss-security/2021/07/20/1 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/torvalds/linux/commit/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.html (opens in a new tab)x_refsource_MISCx_transferred
- http://packetstormsecurity.com/files/163671/Kernel-Live-Patch-Security-Notice-LSN-0079-1.html (opens in a new tab)x_refsource_MISCx_transferred
- https://security.netapp.com/advisory/ntap-20210819-0004/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html (opens in a new tab)x_refsource_MISCx_transferred
- http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html (opens in a new tab)x_refsource_MISCx_transferred
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2022-0015 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-33909)Record last updated .