GitHub Advisoryadvisory · NuGet

GHSA-4j9m-h44m-2hv8 Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding

LOW Published 2026-07-02 Modified 2026-07-02 Official page ↗
Aliases
CVE-2026-50268
Ecosystem
NuGet
Packages
Steeltoe.Configuration.Encryption
Severity
Low
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N
Weaknesses
CWE-256, CWE-327
Reviewed
2026-07-02

Affected packages

• NuGet Steeltoe.Configuration.Encryption: >= 4.0.0, < 4.2.0 → fixed in 4.2.0

Description

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.

Related

Alias · CVE (1)

  • CVE-2026-50268 Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. vulnerability

Weakness · CWE (2)

  • CWE-256 Plaintext Storage of a Password weakness
  • CWE-327 Use of a Broken or Risky Cryptographic Algorithm weakness

References