MEDIUM
The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."
Published Jan 19, 2011
5.0
MEDIUMCVSS 2.0
EPSS 2.52%
Description
The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."
Affected products
No data.
OR
- ≤ 0.2.1.28
- 0.0.2
- 0.0.2_pre13
- 0.0.2_pre14
- 0.0.2_pre15
- 0.0.2_pre16
- 0.0.2_pre17
- 0.0.2_pre18
- 0.0.2_pre19
- 0.0.2_pre20
- 0.0.2_pre21
- 0.0.2_pre22
- 0.0.2_pre23
- 0.0.2_pre24
- 0.0.2_pre25
- 0.0.2_pre26
- 0.0.2_pre27
- 0.0.3
- 0.0.4
- 0.0.5
- 0.0.6
- 0.0.6.1
- 0.0.6.2
- 0.0.7
- 0.0.7.1
- 0.0.7.2
- 0.0.7.3
- 0.0.8
- 0.0.8.1
- 0.0.9
- 0.0.9.1
- 0.0.9.2
- 0.0.9.3
- 0.0.9.4
- 0.0.9.5
- 0.0.9.6
- 0.0.9.7
- 0.0.9.8
- 0.0.9.9
- 0.0.9.10
- 0.1.0.1
- 0.1.0.2
- 0.1.0.3
- 0.1.0.4
- 0.1.0.5
- 0.1.0.6
- 0.1.0.7
- 0.1.0.8
- 0.1.0.9
- 0.1.0.10
- 0.1.0.11
- 0.1.0.12
- 0.1.0.13
- 0.1.0.14
- 0.1.0.15
- 0.1.0.16
- 0.1.0.17
- 0.1.1
- 0.1.1.1
- 0.1.1.1
- 0.1.1.2
- 0.1.1.2
- 0.1.1.3
- 0.1.1.3
- 0.1.1.4
- 0.1.1.4
- 0.1.1.5
- 0.1.1.5
- 0.1.1.6
- 0.1.1.6
- 0.1.1.7
- 0.1.1.7
- 0.1.1.8
- 0.1.1.8
- 0.1.1.9
- 0.1.1.9
- 0.1.1.10
- 0.1.1.10
- 0.1.1.11
- 0.1.1.12
- 0.1.1.13
- 0.1.1.14
- 0.1.1.15
- 0.1.1.16
- 0.1.1.17
- 0.1.1.18
- 0.1.1.19
- 0.1.1.20
- 0.1.1.21
- 0.1.1.22
- 0.1.1.23
- 0.1.1.25
- 0.1.1.26
- 0.1.2.1
- 0.1.2.2
- 0.1.2.3
- 0.1.2.4
- 0.1.2.5
- 0.1.2.5
- 0.1.2.6
- 0.1.2.7
- 0.1.2.8
- 0.1.2.9
- 0.1.2.10
- 0.1.2.11
- 0.1.2.12
- 0.1.2.13
- 0.1.2.14
- 0.1.2.15
- 0.1.2.16
- 0.1.2.17
- 0.1.2.18
- 0.1.2.19
- 0.1.2.30
- 0.1.2.31
- 0.2.0.1
- 0.2.0.2
- 0.2.0.3
- 0.2.0.4
- 0.2.0.5
- 0.2.0.6
- 0.2.0.7
- 0.2.0.8
- 0.2.0.9
- 0.2.0.10
- 0.2.0.11
- 0.2.0.12
- 0.2.0.13
- 0.2.0.14
- 0.2.0.15
- 0.2.0.16
- 0.2.0.17
- 0.2.0.18
- 0.2.0.19
- 0.2.0.20
- 0.2.0.21
- 0.2.0.22
- 0.2.0.23
- 0.2.0.24
- 0.2.0.25
- 0.2.0.26
- 0.2.0.27
- 0.2.0.28
- 0.2.0.29
- 0.2.0.29
- 0.2.0.30
- 0.2.0.30
- 0.2.0.31
- 0.2.0.31
- 0.2.0.32
- 0.2.0.33
- 0.2.0.34
- 0.2.0.35
- 0.2.1.1
- 0.2.1.2
- 0.2.1.3
- 0.2.1.4
- 0.2.1.5
- 0.2.1.6
- 0.2.1.7
- 0.2.1.8
- 0.2.1.9
- 0.2.1.10
- 0.2.1.11
- 0.2.1.12
- 0.2.1.12
- 0.2.1.13
- 0.2.1.14
- 0.2.1.15
- 0.2.1.16
- 0.2.1.17
- 0.2.1.18
- 0.2.1.19
- 0.2.1.20
- 0.2.1.21
- 0.2.1.22
- 0.2.1.23
- 0.2.1.24
- 0.2.1.25
- 0.2.1.26
- 0.2.1.27
- 0.2.2.1
- 0.2.2.1
- 0.2.2.2
- 0.2.2.2
- 0.2.2.3
- 0.2.2.3
- 0.2.2.4
- 0.2.2.4
- 0.2.2.5
- 0.2.2.5
- 0.2.2.6
- 0.2.2.6
- 0.2.2.7
- 0.2.2.8
- 0.2.2.9
- 0.2.2.10
- 0.2.2.11
- 0.2.2.12
- 0.2.2.13
- 0.2.2.14
- 0.2.2.15
- 0.2.2.16
- 0.2.2.17
- 0.2.2.18
- 0.2.2.19
- 0.2.2.20
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
5.0 MEDIUM NVD
AV:N/AC:L/Au:N/C:N/I:N/A:P
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact None
Integrity Impact None
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
2.52% 0.02517
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
EPSS probability 0.02517
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 2.52% (0.02517) | 84.28th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.52% (0.02517) | 82.71th | v5 (v2026.06.15) |
| Mar 17, 2025 | 1.38% (0.01382) | 79.00th | v4 (v2025.03.14) |
| Dec 12, 2024 | 2.28% (0.02279) | 90.03th | v3 (v2023.03.01) |
| Mar 7, 2023 | 2.28% (0.02279) | 87.90th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.32% (0.01319) | 71.27th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.32% (0.01319) | 71.23th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.32% (0.01319) | 69.22th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.32% (0.01319) | 44.98th | v2 (v2022.01.01) |
Weaknesses (1)
References (6)
- http://archives.seul.org/or/announce/Jan-2011/msg00000.html mailing-listx_refsource_MLISTPatch
- http://blog.torproject.org/blog/tor-02129-released-security-patches x_refsource_CONFIRMPatchVendor Advisory
- http://www.securityfocus.com/bid/45953 vdb-entryx_refsource_BID
- https://exchange.xforce.ibmcloud.com/vulnerabilities/64888 vdb-entryx_refsource_XF
- https://gitweb.torproject.org/tor.git/blob/refs/heads/release-0.2.2:/ChangeLog x_refsource_CONFIRMPatch
- https://trac.torproject.org/projects/tor/ticket/2324 x_refsource_CONFIRM
| Link | Providers | Tags |
|---|---|---|
| http://archives.seul.org/or/announce/Jan-2011/msg00000.html | mailing-listx_refsource_MLISTPatch | |
| http://blog.torproject.org/blog/tor-02129-released-security-patches | x_refsource_CONFIRMPatchVendor Advisory | |
| http://www.securityfocus.com/bid/45953 | vdb-entryx_refsource_BID | |
| https://exchange.xforce.ibmcloud.com/vulnerabilities/64888 | vdb-entryx_refsource_XF | |
| https://gitweb.torproject.org/tor.git/blob/refs/heads/release-0.2.2:/ChangeLog | x_refsource_CONFIRMPatch | |
| https://trac.torproject.org/projects/tor/ticket/2324 | x_refsource_CONFIRM |
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Jan 19, 2011
Updated Aug 6, 2024
Reserved Jan 18, 2011
Link CVE-2011-0491
CISA Vulnrichment
Updated n/a