GHSA-4j9m-h44m-2hv8Published

Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

CVE-2026-50268

No KEV entry is attached to this observation; this is not evidence that exploitation is absent.

FIRST EPSS: 0.05 % · percentile 0.00 % · scored 7 Nov 2026.

Observed 07 Nov 2026 16:07:52 UTC · Complete immutable risk JSON

cve-program · CVE-2026-50268

Published

Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.

Source published: 17 Jun 2026 22:01:19 UTC
Source modified: 18 Jun 2026 13:53:58 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

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CVSS 3.1 · 1.9 CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N

euvd · EUVD-2026-37821

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Jun 17, 2026, 10:01:19 PM

dateUpdated: Jun 18, 2026, 1:53:58 PM

Source published: Jun 17, 2026, 10:01:19 PM (timezone not stated)
Source modified: Jun 18, 2026, 1:53:58 PM (timezone not stated)
Observed here: 7 Nov 2026 11:33:27 UTC
Source terms: ENISA EUVD · source terms and attribution apply

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EUVD CVSS 3.1 · 1.9 CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N

nvd · CVE-2026-50268

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Deferred

Weakness classifications: CWE-256 · CWE-327

Original publisher date fields

published: 2026-06-17T23:17:04.730

lastModified: 2026-10-26T11:10:00.157

Source published: 17 Jun 2026 23:17:04 UTC
Source modified: 26 Oct 2026 11:10:00 UTC
Observed here: 27 Oct 2026 13:11:58 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 1.9 CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N

osv · GHSA-4j9m-h44m-2hv8

Published

### Summary Configuring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting. ### Impact Operators who configure `encrypt:rsa:algorithm=OAEP` to obtain CCA2-secure padding receive PKCS#1 v1.5 instead. Currently, `Decrypt()` is called only against operator-controlled configuration data, so no exploitable path exists, but any future code path that exposes a decryption oracle would be Bleichenbacher-vulnerable despite the `OAEP` setting. ### Migration note Existing `{cipher}` values produced under the broken `OAEP` setting were encrypted with PKCS#1 v1.5. The fix makes `OAEP` use actual OAEP padding, so those values will fail to decrypt after upgrading. Re-encrypt all affected `{cipher}` values after upgrading.

Source published: 2 Jul 2026 20:32:21 UTC
Source modified: 2 Jul 2026 20:56:33 UTC
Observed here: 23 Oct 2026 16:01:25 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N

Publisher rating · LOW