CVE-2021-21812
CVE-2021-21812 is a high-severity vulnerability in Att Xmill with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 4.6
- EPSS exploit prediction: 0% (25th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Att Xmill
- Published:
- Last modified:
Description
A stack-based buffer overflow vulnerability exists in the command-line-parsing HandleFileArg functionality of AT&T Labs’ Xmill 0.7. Within the function HandleFileArg the argument filepattern is under control of the user who passes it in from the command line. filepattern is passed directly to strcpy copying the path provided by the user into a static sized buffer without any length checks resulting in a stack-buffer overflow. An attacker can provide malicious input to trigger these vulnerabilities.
Frequently asked questions
- What is CVE-2021-21812?
- A stack-based buffer overflow vulnerability exists in the command-line-parsing HandleFileArg functionality of AT&T Labs’ Xmill 0.7. Within the function HandleFileArg the argument filepattern is under control of the user who passes it in from the command line. filepattern is passed directly to strcpy copying the path provided by the user into a static sized buffer without any length checks resulting in a stack-buffer overflow. An attacker can provide malicious input to trigger these vulnerabilities.
- How severe is CVE-2021-21812?
- CVE-2021-21812 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-21812 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-21812?
- CVE-2021-21812 affects Att Xmill. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-21812?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-21812 published?
- CVE-2021-21812 was published on 2021-08-13 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:att:xmill:0.7:*:*:*:*:*:*:*
More vulnerabilities in Att Xmill
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- CVE-2021-21828 — Critical (CVSS 9.8): A heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs…
- CVE-2021-21827 — Critical (CVSS 9.8): A heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs…
- CVE-2021-21826 — Critical (CVSS 9.8): A heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs…
- CVE-2021-21825 — Critical (CVSS 9.8): A heap-based buffer overflow vulnerability exists in the XML Decompression PlainTextUncompressor::UncompressItem…
All CVEs affecting Att Xmill →
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