CVE-2020-27507: kamailio Classic Buffer Overflow
CVSS: 9.8v3.1CriticalModified
AliasesUBUNTU-CVE-2020-27507DEBIAN-CVE-2020-27507DLA-3438-1
Published 15-03-2023Last modified 27-02-2025
Vulnerability summary
CVE-2020-27507 is a critical (CVSS 9.8) Classic Buffer Overflow vulnerability in kamailio. EPSS estimates a 1.18% chance of exploitation in the next 30 days, higher than 67.1% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)EPSS score
1.18%
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
- 15-03-2023PublishedVulnerability first disclosed.
- 27-02-2025Last modifiedVulnerability information updated.
Description
The Kamailio SIP before 5.5.0 server mishandles INVITE requests with duplicated fields and overlength tag, leading to a buffer overflow that crashes the server or possibly have unspecified other impact.
CVSS metrics
4 scores · 4 sources · 1 versionCritical 9.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
1.18%
Chance of exploitation in the next 30 days
Percentile
67%
Versus all other CVEs
30-day change
0.00 pp
From 1.18% on 19-09-2026
19-09-202619-10-2026
EPSS score1.18%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundKamailio
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Debian1 product
- kamailio< 5.4.2-1 | < 5.2.1-1+deb10u1
Kamailio1 product
- kamailio< 5.5.0
Ubuntu1 product
- kamailio< 4.3.4-1.1ubuntu2.1+esm1 | < 5.1.2-1ubuntu2+esm1 | < 5.3.2-1ubuntu0.1~esm1
3 vendors · 3 products
