CVE-2021-28091
CVE-2021-28091 is a high-severity vulnerability in Entrouvert Lasso with a CVSS 3.x base score of 7.5. 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-347.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-347
- Affected product: Entrouvert Lasso
- Published:
- Last modified:
Description
Lasso all versions prior to 2.7.0 has improper verification of a cryptographic signature.
Frequently asked questions
- What is CVE-2021-28091?
- Lasso all versions prior to 2.7.0 has improper verification of a cryptographic signature.
- How severe is CVE-2021-28091?
- CVE-2021-28091 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
- Is CVE-2021-28091 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-28091?
- CVE-2021-28091 primarily affects Entrouvert Lasso. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-28091?
- 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-2021-28091 published?
- CVE-2021-28091 was published on 2021-06-04 and last updated on 2026-06-17.
References
- http://listes.entrouvert.com/arc/lasso/
- https://git.entrouvert.org/lasso.git/commit/?id=076a37d7f0eb74001127481da2d355683693cde9
- https://git.entrouvert.org/lasso.git/tree/NEWS?id=v2.7.0
- https://lists.debian.org/debian-lts-announce/2021/06/msg00013.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SI4YAQF4VEV2KHQ6OXXZL7CJK7IZQ3EG/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YSVWOHBBWLI2RB5C6TXINFEJRT4YSD3D/
- https://www.debian.org/security/2021/dsa-4926
Affected products (5)
- cpe:2.3:a:entrouvert:lasso:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
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