CVE-2022-32206
Published: 07 July 2022
Summary
CVE-2022-32206 is a medium-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Splunk Universal Forwarder. Its CVSS base score is 6.5 (Medium).
Operationally, ranked in the top 12.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Deeper analysis
CVE-2022-32206 affects curl versions prior to 7.84.0 and stems from unbounded support for chained HTTP compression algorithms in server responses. A malicious server can apply multiple layers of compression using varying algorithms without limit, triggering excessive heap allocations during decompression that manifest as a malloc bomb and produce out-of-memory conditions or crashes.
An attacker operating a malicious HTTP server can trigger the flaw when a curl client fetches a crafted response, requiring no authentication and only user-initiated interaction. Successful exploitation results in high availability impact through resource exhaustion while leaving confidentiality and integrity unaffected, consistent with the CVSS 6.5 rating and CWE-770 classification.
Public advisories referenced in the disclosure, including Siemens and full-disclosure lists, point to the upstream curl 7.84.0 release that introduced a hard limit on decompression chain depth. The associated EPSS scores remained low throughout, with a modest peak of 0.0504 that later receded, indicating limited observed exploitation interest after publication.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-53412
Vulnerability details
curl < 7.84.0 supports "chained" HTTP compression algorithms, meaning that a serverresponse can be compressed multiple times and potentially with different algorithms. The number of acceptable "links" in this "decompression chain" was unbounded, allowing a malicious server to insert a…
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virtually unlimited number of compression steps.The use of such a decompression chain could result in a "malloc bomb", makingcurl end up spending enormous amounts of allocated heap memory, or trying toand returning out of memory errors.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
This control implements explicit throttling on session allocation, addressing the weakness of allocating resources without limits.
Plan testing exercises resource allocation limits and throttling during simulated failures, directly addressing weaknesses that allow unbounded resource use.
Contingency plan updates ensure recovery strategies address unbounded resource allocation, making it harder for attackers to exploit lack of throttling to cause prolonged outages.
Provides continuity when unbounded resource allocation at the primary site leads to exhaustion and downtime.
Alternate services allow operations to continue when primary allocation of resources lacks limits or throttling.
Explicit planning of security-related actions requires defining limits, windows, and resource allocations, making allocation without throttling far less likely.
Measures of performance include tracking allocation behavior and throttling effectiveness, reducing the window for resource exhaustion attacks.
Imposes an inactivity-based limit on network resource allocation, throttling the number of concurrently held connections.