php: dechunk filter integer signedness error causing buffer overflow (MOPS-2010-003)
Published May 7, 2010
9.8
CRITICALCVSS 3.1
EPSS 6.72%
Description
The dechunk filter in PHP 5.3 through 5.3.2, when decoding an HTTP chunked encoding stream, allows context-dependent attackers to cause a denial of service (crash) and possibly trigger memory corruption via a negative chunk size, which bypasses a signed comparison, related to an integer overflow in the chunk size decoder.
Affected products
No data.
Configuration 2
- 11.1
- 11.2
- 11.3
- 10.0
- 11.0
- 11.0
No data.
Red Hat Enterprise Linux 4
php
Not affected
Red Hat Enterprise Linux 5
php
Not affected
Red Hat Enterprise Linux 6
php
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | php | Not affected | n/a |
| Red Hat Enterprise Linux 5 | php | Not affected | n/a |
| Red Hat Enterprise Linux 6 | php | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Not vulnerable. This issue did not affect the versions of php as shipped with Red Hat Enterprise Linux 3, 4, or 5, and Red Hat Application Stack v2.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
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 (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.72% (0.06723) | 93.74th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.72% (0.06723) | 93.08th | v5 (v2026.06.15) |
| Mar 30, 2025 | 1.56% (0.01560) | 79.77th | v4 (v2025.03.14) |
| Mar 29, 2025 | 4.63% (0.04626) | 81.74th | v4 (v2025.03.14) |
| Mar 17, 2025 | 2.16% (0.02160) | 83.12th | v4 (v2025.03.14) |
| Dec 17, 2024 | 3.92% (0.03919) | 91.88th | v3 (v2023.03.01) |
| Feb 9, 2024 | 2.66% (0.02656) | 90.04th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.77% (0.00768) | 80.64th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.77% (0.00768) | 78.43th | v3 (v2023.03.01) |
| Mar 6, 2023 | 4.19% (0.04187) | 87.39th | v2 (v2022.01.01) |
| Apr 1, 2022 | 4.19% (0.04187) | 86.11th | v2 (v2022.01.01) |
| Feb 4, 2022 | 4.19% (0.04187) | 69.86th | v2 (v2022.01.01) |
References (6)
- http://lists.opensuse.org/opensuse-security-announce/2010-09/msg00006.html vendor-advisoryx_refsource_SUSEMailing List
- http://php-security.org/2010/05/02/mops-2010-003-php-dechunk-filter-signed-comparison-vulnerability/index.html x_refsource_MISCBroken LinkExploit
- https://access.redhat.com/security/cve/CVE-2010-1866 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=618167 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2010-1866
- https://www.cve.org/CVERecord?id=CVE-2010-1866
| Link | Providers | Tags |
|---|---|---|
| http://lists.opensuse.org/opensuse-security-announce/2010-09/msg00006.html | vendor-advisoryx_refsource_SUSEMailing List | |
| http://php-security.org/2010/05/02/mops-2010-003-php-dechunk-filter-signed-comparison-vulnerability/index.html | x_refsource_MISCBroken LinkExploit | |
| https://access.redhat.com/security/cve/CVE-2010-1866 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=618167 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2010-1866 | ||
| https://www.cve.org/CVERecord?id=CVE-2010-1866 |
Change history (0)
No recorded changes yet.