CVE-2021-40438Critical KEVConfirmedExploit available
AST
AST
Astra Linux Security Bulletins
Astra publishes per-release bulletins that map upstream CVEs to their own package repositories, with remediation timelines tied to the certification level (SE 1.7, CE 2.12, etc.). Indispensable for systems that require ФСТЭК/ФСБ clearance.
Region
RU
Updates
24 ч
License
Открытые данные
Vendor security bulletins for Astra Linux Special Edition and Common Edition — the primary certified Linux OS for Russian defense and critical infrastructure.
https://wiki.astralinux.ru/pages/viewpage.action?pageId=27362056 →Share link
Anyone with the link can open this vulnerability.
A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Ap…
CVSS
9.0
Critical
EPSS
0.94
p99
Published
2021-01-01
Updated
2021-12-01
Description
A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.
Tags · CWE
KEVPre-auth
CWE-918
CWE-918BaseIncomplete
Server-Side Request Forgery (SSRF)
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
https://cwe.mitre.org/data/definitions/918.html →Open in CWE collection →CAPEC-664
CAPEC-664StandardStable
Server Side Request Forgery
https://capec.mitre.org/data/definitions/664.html →Open in CAPEC collection →
Affected products
Apache2Apache2Apache2Apache2Apache2Apache2Apache2Apache2Apache2HttpdHttpdHttpdHttpdHttpdHttpdHttpdHttpdHttpdHttpdHttpd
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Timeline
2021-01-01
Published
2021-12-01
Added to KEV
2021-12-01
Updated
CVSS 3.1 breakdown
Attack Vector
AV: N
Network (N)
Attack Complexity
AC: H
High (H)
Privileges Required
PR: N
None (N)
User Interaction
UI: N
None (N)
Scope
S: C
Changed (C)
Confidentiality Impact
C: H
High (H)
Integrity Impact
I: H
High (H)
Availability Impact
A: H
High (H)
Exploit indicators
EPSS
0.944 · p99
Known exploited (KEV)
Yes
Known exploits — Сканер-ВС
CVE-2021-40438
cisa · https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Affected software
| Product | Vendor | Status |
|---|---|---|
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| apache2 | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited | |
| httpd | Exploited |
Source databases
AST
AST
Astra Linux Security Bulletins
Astra publishes per-release bulletins that map upstream CVEs to their own package repositories, with remediation timelines tied to the certification level (SE 1.7, CE 2.12, etc.). Indispensable for systems that require ФСТЭК/ФСБ clearance.
Region
RU
Updates
24 ч
License
Открытые данные
Vendor security bulletins for Astra Linux Special Edition and Common Edition — the primary certified Linux OS for Russian defense and critical infrastructure.
https://wiki.astralinux.ru/pages/viewpage.action?pageId=27362056 →DEB
DEB
Debian Security Advisories (DSA)
DSAs are published by the Debian Security Team for issues affecting the stable distribution. The downstream tracker (security-tracker.debian.org) additionally maps every CVE to its package-level status across all supported suites.
Region
Intl.
Updates
1 ч
License
Public Domain
Advisories covering the Debian stable and oldstable releases. Ship notes include the exact .deb version that remediates each issue.
https://www.debian.org/security/ →CVE
CVE
National Vulnerability Database
NVD is the U.S. government repository of standards-based vulnerability management data, built on top of the MITRE CVE list. Every record includes CPE applicability statements, CVSS v2 and v3.x base scores, CWE mappings and cross-references to advisories.
Region
US
Updates
15 min
License
Public Domain
Comprehensive catalog of publicly disclosed vulnerabilities with CPE matches, CVSS scoring and reference URLs. De-facto standard for cross-vendor correlation.
https://nvd.nist.gov →RED
RED
Red Hat Security Advisories (RHSA)
Red Hat advisories are authoritative for RHEL-family systems: each record lists the exact package NEVRA fixed, the affected streams, and a Red Hat-assigned severity that may differ from NVD's. Many downstream projects (CentOS Stream, Rocky, Alma) follow these IDs.
Region
US
Updates
1 ч
License
CC BY-SA 4.0
Advisories for Red Hat Enterprise Linux, OpenShift, Ansible and other Red Hat products. Includes detailed backport tracking — critical for long-term-support distributions.
https://access.redhat.com/security/security-updates/ →UBU
UBU
Ubuntu Security Notices (USN)
USNs are authoritative for Ubuntu systems. The CVE Tracker links each vulnerability to its per-release status (needed, released, not-affected) and to the exact Launchpad bug where the fix is integrated.
Region
Intl.
Updates
1 ч
License
CC BY-SA 3.0
Security notices for Ubuntu LTS and interim releases, covering main, universe and (via Pro) ESM-extended packages.
https://ubuntu.com/security/notices →Related vulnerabilities