CVE-2021-28902: cesnet libyang Unchecked Return Value
CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2021-28902DEBIAN-CVE-2021-28902
Published 20-05-2021Last modified 03-08-2024
Vulnerability summary
CVE-2021-28902 is a high (CVSS 7.5) Unchecked Return Value vulnerability in cesnet libyang. EPSS estimates a 1.55% chance of exploitation in the next 30 days, higher than 74.7% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
7.5/10
010
High · v3.1 (NVD)EPSS score
1.55%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 20-05-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
In function read_yin_container() in libyang <= v1.0.225, it doesn't check whether the value of retval->ext[r] is NULL. In some cases, it can be NULL, which leads to the operation of retval->ext[r]->flags that results in a crash.
CVSS metrics
4 scores · 3 sources · 2 versionsHigh 7.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Medium 5.0Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:N/I:N/A:PSourcesSingle source
EPSS trend
Probability
1.55%
Chance of exploitation in the next 30 days
Percentile
75%
Versus all other CVEs
30-day change
0.00 pp
From 1.55% on 19-09-2026
19-09-202619-10-2026
EPSS score1.55%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundLibyang
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Cesnet1 product
- libyang≤ 1.0.225
Debian1 product
- libyang< 3.4.2+dfsg-2
Ubuntu1 product
- libyangAll versions (No fix recorded)
3 vendors · 3 products
References
5 links- github.com/CESNET/libyang/issues/1454X Refsource CONFIRMREPORTExploitIssue TrackingThird Party Advisory
