A stack overflow in libyang <= v1.0.225 can cause a denial of service through function…
Priority LOW 37CWE-674Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Will not fix Red Hat: no fix planned
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-674.
Summary
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.
Why it matters now
EPSS 0.02425 84th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Will not fix Red Hat: no fix planned
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Will not fix |
Not affected: 1 product
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-28903
- 2026-10-03 Alias added: GHSA-vr34-263x-7q3r
References
Advisory 1
More CESNET Libyang vulnerabilities
- TI-2023-11820 libyang from v2.0.164 to v2.1.30 was discovered to contain a NULL pointer dereference via… CVSS 3.1HIGH 7.5
- TI-2019-13946 Stack-based buffer overflow in Red Hat libyang CVSS 3.1CRITICAL 9.8
- TI-2019-13945 Stack-based buffer overflow in Red Hat libyang CVSS 3.1CRITICAL 9.8
- TI-2019-14631 A double-free is present in libyang before v1.0-r1 in the function yyparse() when an… CVSS 3.1HIGH 8.8
- TI-2019-14628 A double-free is present in libyang before v1.0-r3 in the function yyparse() when a type… CVSS 3.1HIGH 8.8
- TI-2019-14627 A double-free is present in libyang before v1.0-r1 in the function yyparse() when an… CVSS 3.1HIGH 8.8
Sources
- CVE-2021-28903 · CVE Program
- CVE-2021-28903 · NVD
- FIRST EPSS
- GHSA-vr34-263x-7q3r · GitHub Advisory Database · CC BY 4.0
- CVE-2021-28903 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences