Vulnerability · Published Sep 16, 2021 · Assigned by apache
CVE-2021-39275ap_escape_quotes buffer overflow
Critical 9.8
In plain English
A critical-severity security flaw in Apache HTTP Server from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 39.4% (higher than 99% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)9.8Critical
Exploit odds (30 days)39.4%top 1.4% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
ap_escape_quotes() may write beyond the end of a buffer when given malicious input. No included modules pass untrusted data to these functions, but third-party / external modules may. This issue affects Apache HTTP Server 2.4.48 and earlier.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | httpd | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | httpd-devel | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | httpd-filesystem | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | httpd-manual | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | httpd-tools | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | mod_ldap | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | mod_md | 1:2.0.8-8.module_el8.6.0+2872+fe0ff7aa | ALSA-2022:0891 |
| AlmaLinux:8 | mod_proxy_html | 1:2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | mod_session | 2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| AlmaLinux:8 | mod_ssl | 1:2.4.37-43.module_el8.5.0+2630+51c6d843.2.alma | ALSA-2022:0891 |
| Alpine:v3.20 | apache2 | 2.4.49-r0 | ALPINE-CVE-2021-39275 |
| Alpine:v3.21 | apache2 | 2.4.49-r0 | ALPINE-CVE-2021-39275 |
| Alpine:v3.22 | apache2 | 2.4.49-r0 | ALPINE-CVE-2021-39275 |
| Alpine:v3.23 | apache2 | 2.4.49-r0 | ALPINE-CVE-2021-39275 |
| Alpine:v3.24 | apache2 | 2.4.49-r0 | ALPINE-CVE-2021-39275 |
| Debian:12 | apache2 | 2.4.49-1 | DEBIAN-CVE-2021-39275 |
| Debian:13 | apache2 | 2.4.49-1 | DEBIAN-CVE-2021-39275 |
| Debian:14 | apache2 | 2.4.49-1 | DEBIAN-CVE-2021-39275 |
| Rocky Linux:8 | httpd | 0:2.4.37-43.module+el8.5.0+714+5ec56ee8 | RLSA-2022:0891 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-3.module+el8.5.0+695+1fa8055e | RLSA-2022:0891 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-3.module+el8.4.0+553+7a69454b | RLSA-2022:0891 |
| Rocky Linux:8 | mod_md | 1:2.0.8-8.module+el8.5.0+695+1fa8055e | RLSA-2022:0891 |
| Rocky Linux:8 | mod_md | 1:2.0.8-8.module+el8.4.0+553+7a69454b | RLSA-2022:0891 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache HTTP Server | Apache HTTP Server 2.4 – through 2.4.48 |
References
- https://httpd.apache.org/security/vulnerabilities_24.html x_refsource_MISC
- FEDORA-2021-dce7e7738e vendor-advisory, x_refsource_FEDORA
- [httpd-users] 20210923 [users@httpd] 2.4.49 security fixes: more info mailing-list, x_refsource_MLIST
- [httpd-users] 20210923 Re: [users@httpd] 2.4.49 security fixes: more info mailing-list, x_refsource_MLIST
- [httpd-users] 20210923 [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info mailing-list, x_refsource_MLIST
- [httpd-users] 20210923 Re: [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info mailing-list, x_refsource_MLIST
- FEDORA-2021-e3f6dd670d vendor-advisory, x_refsource_FEDORA
- [debian-lts-announce] 20211002 [SECURITY] [DLA 2776-1] apache2 security update mailing-list, x_refsource_MLIST
- DSA-4982 vendor-advisory, x_refsource_DEBIAN
- 20211124 Multiple Vulnerabilities in Apache HTTP Server Affecting Cisco Products: November 2021 vendor-advisory, x_refsource_CISCO
- https://www.oracle.com/security-alerts/cpujan2022.html x_refsource_MISC
- https://security.netapp.com/advisory/ntap-20211008-0004/ x_refsource_CONFIRM
- https://www.oracle.com/security-alerts/cpuapr2022.html x_refsource_MISC
- https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdf x_refsource_CONFIRM
- GLSA-202208-20 vendor-advisory, x_refsource_GENTOO