CVE-2025-0693: aws aws sign-in iam login flow Observable Response Discrepancy
CVSS: 6.9v4.0MediumDeferred
Published 23-01-2025Last modified 14-10-2025
Vulnerability summary
CVE-2025-0693 is a medium (CVSS 6.9) Observable Response Discrepancy vulnerability in aws aws sign-in iam login flow. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 29.2% of scored vulnerabilities.
CVSS score
6.9/10
010
Medium · v4.0 (CVE.org)EPSS score
0.37%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 23-01-2025PublishedVulnerability first disclosed.
- 14-10-2025Last modifiedVulnerability information updated.
Description
Variable response times in the AWS Sign-in IAM user login flow allowed for the use of brute force enumeration techniques to identify valid IAM usernames in an arbitrary AWS account.
CVSS metrics
4 scores · 2 sources · 2 versionsMedium 6.9Preferred score · CVE.org (CNA)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NSourcesAll 2 agree
- NVDNIST6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/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
Medium 5.3Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NSourcesAll 2 agree
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS trend
Probability
0.37%
Chance of exploitation in the next 30 days
Percentile
29%
Versus all other CVEs
30-day change
0.00 pp
From 0.37% on 19-09-2026
19-09-202619-10-2026
EPSS score0.37%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-204Observable Response DiscrepancyThe product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere.
- CWE-208Observable Timing DiscrepancyTwo separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.
Affected systems
Aws1 product
1 vendor · 1 product
References
1 links- aws.amazon.com/security/security-bulletins/AWS-2025-002/Vendor Advisory