EUVD-2026-32040
GHSA-g7jq-j257-rww2
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from Vendor (mitre).
CVSS VectorVendor: mitre
Lifecycle Timeline
1DescriptionCVE.org
In OpenStack Swift before 2.36.2 and 2.37.2, s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request body. The StreamingInput class repeatedly appends an empty buffer and re-reads, causing the proxy-server worker handling the request to become permanently unresponsive with increasing CPU and memory consumption. An authenticated attacker can systematically exhaust all proxy-server workers, resulting in denial of service. The defect was introduced in Swift 2.36.0.
AnalysisAI
Denial of service in OpenStack Swift's s3api middleware allows an authenticated S3 API user to permanently hang proxy-server workers by sending a truncated aws-chunked PUT request body. Versions 2.36.0 through 2.36.1 and 2.37.0 through 2.37.1 are affected; the defect was introduced in 2.36.0 and fixed in 2.36.2 and 2.37.2. There is no public exploit identified at time of analysis, and EPSS is very low (0.04%, 12th percentile), but the high availability impact and low attack complexity make this a credible operational threat to S3-compatible Swift deployments.
Technical ContextAI
OpenStack Swift is a distributed object storage system; its s3api middleware provides an Amazon S3-compatible REST interface on the proxy-server tier. AWS chunked uploads (the aws-chunked content encoding) frame the request body into length-prefixed chunks that the StreamingInput class reads incrementally. The flaw is a CWE-835 (Loop with Unreachable Exit Condition / 'infinite loop'): when the chunked body is truncated, StreamingInput repeatedly appends an empty buffer and re-reads instead of detecting end-of-stream or erroring out, so the loop never terminates. The single CPE (cpe:2.3:a:openstack:swift) confirms the OpenStack Swift application package is the affected component, specifically the proxy-server worker process handling the malformed request.
RemediationAI
Vendor-released patch: upgrade to Swift 2.36.2 (for the 2.36.x line) or 2.37.2 (for the 2.37.x line), which contain the fix; deployments on 2.35.x and earlier are unaffected and do not regress. The corrective changes are tracked in Gerrit at https://review.opendev.org/c/openstack/swift/+/987957 and https://review.opendev.org/c/openstack/swift/+/988093, with background at https://bugs.launchpad.net/bugs/2152205 and the oss-security disclosure at http://www.openwall.com/lists/oss-security/2026/05/27/9. If immediate patching is not possible, compensating controls include disabling or restricting the s3api middleware in the proxy-server pipeline where the S3-compatible interface is not required (trade-off: breaks all S3 API clients), and placing a reverse proxy or WAF in front of the proxy-server to enforce request body completeness and Content-Length consistency for aws-chunked uploads (trade-off: chunked-encoding validation is non-trivial and may reject some legitimate streaming clients). Operationally, monitor proxy-server workers for stuck threads with rising CPU/memory and configure worker recycling/timeouts so hung workers are reaped, and rate-limit or revoke credentials of abusive authenticated clients (trade-off: does not close the root cause).
Oracle MySQL through 5.5.52, 5.6.x through 5.6.33, and 5.7.x through 5.7.15; MariaDB before 5.5.51, 10.0.x before 10.0.2
Eval injection vulnerability in the create method in the Bookmarks controller in Foreman before 1.2.0-RC2 allows remote
The create method in app/controllers/users_controller.rb in Foreman before 1.2.0-RC2 allows remote authenticated users w
Systems with microprocessors utilizing speculative execution and speculative execution of memory reads before the addres
The Floppy Disk Controller (FDC) in QEMU, as used in Xen 4.5.x and earlier and KVM, allows local guest users to cause a
Memory Corruption was discovered in the cmsgpack library in the Lua subsystem in Redis before 3.2.12, 4.x before 4.0.10,
The IPTables firewall in OpenStack Neutron before 7.0.4 and 8.0.0 through 8.1.0 allows remote attackers to bypass an int
An issue in OpenStack magnum yoga-eom version allows a remote attacker to execute arbitrary code via the cert_manager.py
An Integer Overflow issue was discovered in the struct library in the Lua subsystem in Redis before 3.2.12, 4.x before 4
glibc contains a vulnerability that allows specially crafted LD_LIBRARY_PATH values to manipulate the heap/stack, causin
Buffer overflow in the pcnet_receive function in hw/net/pcnet.c in QEMU, when a guest NIC has a larger MTU, allows remot
Code injection in OpenStack Vitrage query parser allows authenticated users to execute arbitrary Python code through cra
Same technique Denial Of Service
View allVendor StatusVendor
Share
External POC / Exploit Code
Leaving vuln.today