Crafted class files exhaust CPU in OW2 ASM ClassWriter
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 fixed, 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-407.
Summary
OW2 ASM from 3.0 before 9.11 contains a denial of service flaw (CWE-407) in its unbounded frame computation fixed-point algorithm. A local attacker with no privileges can supply crafted class files that make the algorithm converge slowly when a user processes them with ClassWriter.COMPUTE_FRAMES, tying up transforming threads and exhausting CPU for an unbounded time.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
Description from the CNA
OW2 ASM 3.0 before 9.11 contains a denial of service vulnerability that allows attackers to exhaust CPU by supplying crafted class files processed with ClassWriter.COMPUTE_FRAMES. Attackers can craft methods that make the unbounded MethodWriter.computeAllFrames() fix point algorithm converge slowly, tying up transforming threads for unbounded time.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade OW2 ASM to version 9.11, which fixes the flaw. Red Hat fixes Red Hat Hardened Images in advisory RHSA-2026:83847. Red Hat lists Red Hat build of Quarkus as affected with no fix plan available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
- Fix · CNA ASM (OW2) Fixed in 9.11
Red Hat 1 advisory
- RHSA-2026:83847 Released 2026-10-16 · Red Hat rating ModerateRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images maven3.9-3.9.16-0.4.hum1@noarch@public-hummingbird-aarch64-rpms, maven3.9-3.9.16-0.4.hum1@noarch@public-hummingbird-s390x-rpms, maven3.9-3.9.16-0.4.hum1@noarch@public-hummingbird-x86_64-rpms +4
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
OW2 ASM 9.11
9 records Highest priority Priority LOW 9 LOW
Other records, highest priority first
- TI-2026-74085 Excessive resource consumption in OW2 ASM Analyzer allows denial of servicePriority LOW 29
- TI-2026-74084 Exponential memory allocation in OW2 ASM JSRInlinerAdapterPriority LOW 29
- TI-2026-74083 Uncontrolled recursion in OW2 ASM SignatureReader enables denial of servicePriority LOW 29
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat build of Quarkus | Affected | No fix yet |
| Red Hat Hardened Images | Fixed | RHSA-2026:83847 |
Timeline
- 2026-10-14 Threatist record created from CVE-2026-110261
- 2026-10-14 Alias added: GHSA-42q2-x6j4-w994
- 2026-10-15 CISA SSVC decision points changed
- 2026-10-15 Priority changed: MEDIUM → LOW
- 2026-10-20 Fix available: RHSA-2026:83847 · Red Hat
- 2026-10-20 Fix available: Red Hat Hardened Images · Red Hat
- 2026-10-20 CVSS score added · Red Hat
- 2026-11-02 Affected versions changed · Red Hat
References
More OW2 vulnerabilities
- TI-2026-76174 Infinite loop in OW2 ASM Label.resolve() enables denial of service CVSS 4.0MEDIUM 6.8
- TI-2026-74085 Excessive resource consumption in OW2 ASM Analyzer allows denial of service CVSS 4.0MEDIUM 6.8
- TI-2026-74084 Exponential memory allocation in OW2 ASM JSRInlinerAdapter CVSS 4.0MEDIUM 6.8
- TI-2026-74083 Uncontrolled recursion in OW2 ASM SignatureReader enables denial of service CVSS 4.0MEDIUM 6.8
- TI-2026-74080 Quadratic memory allocation in OW2 ASM exception handlers CVSS 4.0MEDIUM 6.8
- TI-2026-74079 Uncontrolled recursion in OW2 ASM allows denial of service CVSS 4.0MEDIUM 6.8
Sources
- CVE-2026-110261 · CVE Program
- CVE-2026-110261 · NVD
- FIRST EPSS
- GHSA-42q2-x6j4-w994 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-110261 · 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