CVE-2021-34798
NULL pointer dereference in httpd core
Exploitation likely. EPSS gives it a 65% chance of exploitation in the next 30 days. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
Multiple vulnerabilities were identified in the Apache HTTP Server software. These include NULL Pointer Dereferencing, Out-of-bounds Write and Server-Side Request Forgery related vulnerabilities. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends specific countermeasures for products where updates are not, or not yet available.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
65% chance of exploitation activity in the next 30 days, which ranks it in the 99th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 1743 days, from the signal feeds we watch.
- OpenVAS check added
- EPSS band changemoderate → high
- Nuclei check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
- communications cloud native core network function cloud native environmentDatabases / data-warehouse-analytics
- enterprise manager base platformEnterprise Software / itsm-monitoring
- http serverWeb & CMS Plugins
- instantis enterprisetrackEnterprise Software / itsm-monitoring
- peoplesoft enterprise peopletoolsEnterprise Software / itsm-monitoring
- zfs storage appliance kitDatabases / data-warehouse-analytics
And 13 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 7.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- httpd.apache.org/security/vulnerabilities_24.html&
- lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432@%3Cusers.httpd.apache.org%3E&
- lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c@%3Cusers.httpd.apache.org%3E&
And 49 more references. See all after sign-in
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