CVE-2021-40438
Apache — Apache HTTP Server-Side Request Forgery (SSRF)
Apache · CWE-918 — Server-side request forgery · in CISA KEV since 2021-12-01
EVRS 93 of 100 Immediate
Out-of-Band / Urgent Remediation
Rank 71 of 2,960 tracked
Why it scores 93
Evidence available: 6 of 7 signalsListed in the CISA KEV catalog, and associated with known ransomware campaigns.
- CISA KEVApplied
- RansomwareApplied
- Vendor exploitationDid not apply
- EPSSApplied
- Microsoft Exploitability IndexNot applicable
- Pre-patch disclosureNo data
- KEV recencyDid not apply
- CVSSApplied
The band answers “how soon”, not “how bad”. No data for: Pre-patch disclosure. Why some signals show no data
Fix
Patch or fixed version identifiedCISA required action
Fixed in
apache2 -> 2.4.29-1ubuntu4.18 | apache2 -> 2.4.41-4ubuntu3.6 | apache2 -> 2.4.18-2ubuntu3.17+esm3 | apache2 -> 2.4.49-1
Affected versions
- jboss core services
1.0 - software collections
1.0 - http server
<= 2.4.4812.2.1.3.012.2.1.4.0 - cloud backup
- clustered data ontap
- storagegrid
- enterprise manager ops center
12.4.0.0 - instantis enterprisetrack
17.117.217.3
+31 more affected products; see the full list at NVD.
Remediation
Apply updates per vendor instructions.
Fixed versions from NVD.
Evidence
Each value with its source| Measure | Value | Source |
|---|---|---|
| CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. | 9.0 | NVD |
| FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. | 0.999 (99.99th pctl) | FIRST EPSS |
| Actively exploitedWhether a source of record has confirmed attacks using it in the wild. | Confirmed | CISA KEV |
| Ransomware campaign useWhether CISA has seen ransomware operators use it. | Known | CISA KEV |
| CISA remediation deadlineThe date US federal agencies must have fixed or mitigated it. | 2021-12-15 · KEV since 2021 · listed over a year | CISA KEV |
| Public exploit moduleA module existing is not the same as active exploitation. | None known | Metasploit |
| EUVD cross-referenceENISA's record: CVSS 9.0 (v3.1), assigned by apache. | Listed | ENISA EUVD |
Description
NVDA 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.
What CISA says to do
