Improper handling of exceptional conditions in Tor
Priority LOW 37CWE-755Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
buf_pullup in Tor before 0.2.4.26 and 0.2.5.x before 0.2.5.11 does not properly handle unexpected arrival times of buffers with invalid layouts, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via crafted packets.
Why it matters now
EPSS 0.02185 82nd percentileScored 2026-11-07
Fix Fixed Tor (The Tor Project): 0.2.4.26, 0.2.5.11
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 |
|---|---|---|---|---|---|
| The Tor Project | Tor | before 0.2.4.26; 0.2.5 to before 0.2.5.11 | 0.2.4.26, 0.2.5.11 | Patch available | CNA |
- Tor VendorThe Tor Project Affected before 0.2.4.26; 0.2.5 to before 0.2.5.11 Fixed in 0.2.4.26, 0.2.5.11 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* | before 0.2.4.26; 0.2.5.1 to before 0.2.5.11 | Vulnerable | torproject |
- cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* Versions before 0.2.4.26; 0.2.5.1 to before 0.2.5.11 Vulnerable ·torproject
Remediation
- Fix · CNA Tor (The Tor Project) Fixed in 0.2.4.26, 0.2.5.11
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2015-2688
- 2026-10-03 Alias added: GHSA-9h72-qxgr-5j87
References
More The Tor Project vulnerabilities
- TI-2017-06332 Use after free in Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before… CVSS 3.0HIGH 8.1
- TI-2017-06330 Memory corruption in Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9… CVSS 3.0HIGH 7.5
- TI-2017-06328 In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0… CVSS 3.0HIGH 7.5
- TI-2015-02373 Improper input validation in Tor CVSS 3.1HIGH 7.5
- TI-2017-06329 NULL pointer dereference in Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17… CVSS 3.0HIGH 7.5
- TI-2015-02583 The Hidden Service (HS) server implementation in Tor before 0.2.4.27, 0.2.5.x before… CVSS 3.1HIGH 7.5
Sources
- CVE-2015-2688 · CVE Program
- CVE-2015-2688 · NVD
- FIRST EPSS
- GHSA-9h72-qxgr-5j87 · GitHub Advisory Database · CC BY 4.0
- CVE-2015-2688 · 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