CVE-2021-28903
CVE-2021-28903 is a high-severity vulnerability in Cesnet Libyang 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-674.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (82nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-674
- Affected product: Cesnet Libyang
- Published:
- Last modified:
Description
A stack overflow in libyang <= v1.0.225 can cause a denial of service through function lyxml_parse_mem(). lyxml_parse_elem() function will be called recursively, which will consume stack space and lead to crash.
Frequently asked questions
- What is CVE-2021-28903?
- A stack overflow in libyang <= v1.0.225 can cause a denial of service through function lyxml_parse_mem(). lyxml_parse_elem() function will be called recursively, which will consume stack space and lead to crash.
- How severe is CVE-2021-28903?
- CVE-2021-28903 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 none, and availability high.
- Is CVE-2021-28903 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-28903?
- CVE-2021-28903 affects Cesnet Libyang. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-28903?
- 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-2021-28903 published?
- CVE-2021-28903 was published on 2021-05-20 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:cesnet:libyang:*:*:*:*:*:*:*:*
More vulnerabilities in Cesnet Libyang
- CVE-2019-19334 — Critical (CVSS 9.8): In all versions of libyang before 1.0-r5, a stack-based buffer overflow was discovered in the way libyang parses YANG…
- CVE-2019-19333 — Critical (CVSS 9.8): In all versions of libyang before 1.0-r5, a stack-based buffer overflow was discovered in the way libyang parses YANG…
- CVE-2019-20397 — High (CVSS 8.8): A double-free is present in libyang before v1.0-r1 in the function yyparse() when an organization field is not…
- CVE-2019-20394 — High (CVSS 8.8): A double-free is present in libyang before v1.0-r3 in the function yyparse() when a type statement in used in a…
- CVE-2019-20393 — High (CVSS 8.8): A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used.…
- CVE-2023-26917 — High (CVSS 7.5): libyang from v2.0.164 to v2.1.30 was discovered to contain a NULL pointer dereference via the function…
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