CVE-2026-103119
CRITICAL 9.1Buffer under-read vulnerability in Apache Tomcat meant that a large non-blocking write could result in the response body being split between the current request and the next request received on that connection leading most likely to failure of the second request and possibly leakage of data from the first response to the second. This issue affects Apache Tomcat: from 11.0.0-M25 through 11.0.26. Users are recommended to upgrade to version 11.0.27, which fixes the issue.
Severe if exploited (CVSS 9.1), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
—EPSS not yet scored
Impact if exploited
9.1CVSS 3.1 · CRITICAL
- ConfidentialityHigh
- IntegrityNone
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-103119/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-103119/poc.json
Weakness (CWE)
- CWE-127: Buffer under-read
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
All CVSS metrics
- CRITICAL 9.1 v3.1 · ADP Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - CRITICAL 9.1 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H