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Medium

OpenStack Keystone EC2 API AWS Signature V4 Replay Due to Missing TTL Check

IdentifiersCVE-2020-12692CWE-294· Authentication Bypass by…

CVE-2020-12692 affects OpenStack Keystone before 15.0.1 and 16.0.0. The vulnerability is in Keystone's EC2 credential authentication handling for the EC2 API, where AWS Signature Version 4 requests are accepted without enforcing a signature time-to-live (TTL) check. Because the Authorization header can be replayed after capture, a previously valid signed request can be reused to obtain a new OpenStack token repeatedly. The issue is specifically described as allowing an attacker who can sniff the Authorization header to reissue an OpenStack token an unlimited number of times.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows unauthorized reuse of captured AWS Signature V4 authentication material against Keystone's EC2 API. An attacker can replay a sniffed Authorization header to repeatedly obtain OpenStack tokens associated with the victim, resulting in unauthorized access and persistent token reissuance without needing the victim's secret material beyond the captured header. This can enable continued impersonation of the affected identity and access to resources permitted to that account.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, reduce exposure of the Keystone EC2 API to untrusted networks, enforce transport security to reduce the chance of Authorization header capture, and monitor for anomalous or repeated token issuance via the EC2 authentication path. Limiting access to the affected endpoint and rotating exposed credentials may reduce risk, but the definitive fix is upgrading to a patched Keystone release.

Remediation

Patch, then assume compromise.

Upgrade OpenStack Keystone to a fixed release. The provided advisory indicates affected versions are Keystone before 15.0.1 and 16.0.0, and remediation is to update to 15.0.1 or later in the 15.x series, or to 16.0.0 or later, as applicable in the deployment.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
CanonicalUbuntu Linuxapplication
OpenstackKeystoneapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

1 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

1 SOURCESView more in app
What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

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Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2020-12692
NVD
nvd.nist.gov/vuln/detail/CVE-2020-12692
MITRE CWE · CWE-294
Authentication Bypass by Capture-replay
Vendor Advisory
security.openstack.org/ossa/OSSA-2020-003.html
Third Party Advisory
openwall.com/lists/oss-security/2020/05/07/1
Third Party Advisory
bugs.launchpad.net/keystone/+bug/1872737
Third Party Advisory
usn.ubuntu.com/4480-1
Third Party Advisory
openwall.com/lists/oss-security/2020/05/06/4