CVE-2025-24898: rust-openssl ssl :select_next_proto Use After Free Vulnerability

MODERATE
Advisory Identifier: GHSA-rpmj-rpgj-qmpm
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CWE-416
Published
Advisory Summary

CVE-2025-24898 is a MODERATE :select_next_proto use after free vulnerability (CWE-416: Use After Free) affecting rust-openssl ssl libraries in the crates.io ecosystem. The issue involves :select_next_proto use after free. Remediation is available by upgrading affected packages to version 0.10.70.

CVE-2025-24898 at a Glance

CVE Identifier CVE-2025-24898
GHSA Identifier GHSA-rpmj-rpgj-qmpm
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-416: Use After Free
Affected Product rust-openssl ssl
Package Ecosystem crates.io
Published Date
Last Updated

How to Fix CVE-2025-24898

To remediate this vulnerability, upgrade all affected rust-openssl ssl dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

openssl fixed: 0.10.70 
Upgrade openssl to 0.10.70
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for openssl

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-24898, inspect your project dependencies for rust-openssl ssl:

inspect dependencies for openssl

Analyze the terminal output to locate any version of rust-openssl ssl in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.10.70), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-416: Use After Free, where the product reuses or references memory after it has been freed. at some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. In rust-openssl ssl, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact `ssl::select_next_proto` can return a slice pointing into the `server` argument's buffer but with a lifetime bound to the `client` argument. In situations where the `server` buffer's lifetime is shorter than the `client` buffer's, this can cause a use after free. This could cause the server to crash or to return arbitrary memory contents to the client. ### Patches `openssl` 0.10.70 fixes the signature of `ssl::select_next_proto` to properly constrain the output buffer's lifetime to that of both input buffers. ### Workarounds In standard usage of `ssl::select_next_proto` in the callback passed to `SslContextBuilder::set_alpn_select_callback`, code is only affected if the `server` buffer is constructed *within* the callback. For example: Not vulnerable - the server buffer has a `'static` lifetime: ```rust builder.set_alpn_select_callback(|_, client_protos| { ssl::select_next_proto(b"\x02h2", client_protos).ok_or_else(AlpnError::NOACK) }); ``` Not vulnerable - the server buffer outlives the handshake: ```rust let server_protos = b"\x02h2".to_vec(); builder.set_alpn_select_callback(|_, client_protos| { ssl::select_next_proto(&server_protos, client_protos).ok_or_else(AlpnError::NOACK) }); ``` Vulnerable - the server buffer is freed when the callback returns: ```rust builder.set_alpn_select_callback(|_, client_protos| { let server_protos = b"\x02h2".to_vec(); ssl::select_next_proto(&server_protos, client_protos).ok_or_else(AlpnError::NOACK) }); ``` ### References https://github.com/sfackler/rust-openssl/pull/2360

CVE-2025-24898 Affected rust-openssl ssl Versions

1 component(s)
Fixed Versions:
0.10.70
Product / Package Ecosystem Affected Versions Fixed Version
openssl
 crates.io
≥ 0.10.0
< 0.10.70
0.10.70

References

GitHub Advisory / Wiki ADVISORY
https://github.com/sfackler/rust-openssl/security/advisories/GHSA-rpmj-rpgj-qmpm
NVD — CVE-2025-24898 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-24898
rust-openssl ssl Source Repository REPOSITORY
https://github.com/sfackler/rust-openssl/pull/2360
Security Fix Commit FIX COMMIT
https://github.com/sfackler/rust-openssl/commit/f014afb230de4d77bc79dea60e7e58c2f47b60f2
crates.io/crates/openssl WEB
https://crates.io/crates/openssl
rust-openssl ssl Source Repository REPOSITORY
https://github.com/sfackler/rust-openssl
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2025/02/msg00009.html
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2025-0004.html

Frequently Asked Questions

What is CVE-2025-24898?
CVE-2025-24898 is a security vulnerability in rust-openssl ssl involving :select_next_proto use after free under CWE-416: Use After Free.
Which rust-openssl ssl versions are affected?
Affected versions include releases prior to 0.10.70 across affected packages: openssl.
What version fixes CVE-2025-24898?
Upgrading to 0.10.70 (or the latest patched release for your respective branch) resolves the vulnerability.
Is openssl affected?
Yes, openssl is affected in releases prior to 0.10.70. Upgrade your dependency to 0.10.70 or later.
What CWE is associated with CVE-2025-24898?
CVE-2025-24898 is classified under CWE-416: Use After Free (The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.).
How can I check crates.io dependencies for CVE-2025-24898?
Run the dependency tree command: 'inspect dependencies for openssl'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rpmj-rpgj-qmpm",
  "modified" : "2025-02-11T09:30:32Z",
  "published" : "2025-02-03T17:56:46Z",
  "aliases" : [ "CVE-2025-24898" ],
  "summary" : "rust-openssl ssl::select_next_proto use after free",
  "details" : "### Impact\n`ssl::select_next_proto` can return a slice pointing into the `server` argument's buffer but with a lifetime bound to the `client` argument. In situations where the `server` buffer's lifetime is shorter than the `client` buffer's, this can cause a use after free. This could cause the server to crash or to return arbitrary memory contents to the client.\n\n### Patches\n`openssl` 0.10.70 fixes the signature of `ssl::select_next_proto` to properly constrain the output buffer's lifetime to that of both input buffers.\n\n### Workarounds\nIn standard usage of `ssl::select_next_proto` in the callback passed to `SslContextBuilder::set_alpn_select_callback`, code is only affected if the `server` buffer is constructed *within* the callback. For example:\n\nNot vulnerable - the server buffer has a `'static` lifetime:\n```rust\nbuilder.set_alpn_select_callback(|_, client_protos| {\n    ssl::select_next_proto(b\"\\x02h2\", client_protos).ok_or_else(AlpnError::NOACK)\n});\n```\n\nNot vulnerable - the server buffer outlives the handshake:\n```rust\nlet server_protos = b\"\\x02h2\".to_vec();\nbuilder.set_alpn_select_callback(|_, client_protos| {\n    ssl::select_next_proto(&server_protos, client_protos).ok_or_else(AlpnError::NOACK)\n});\n```\n\nVulnerable - the server buffer is freed when the callback returns:\n```rust\nbuilder.set_alpn_select_callback(|_, client_protos| {\n    let server_protos = b\"\\x02h2\".to_vec();\n    ssl::select_next_proto(&server_protos, client_protos).ok_or_else(AlpnError::NOACK)\n});\n```\n\n### References\nhttps://github.com/sfackler/rust-openssl/pull/2360",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "openssl"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.10.0"
      }, {
        "fixed" : "0.10.70"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/sfackler/rust-openssl/security/advisories/GHSA-rpmj-rpgj-qmpm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-24898"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sfackler/rust-openssl/pull/2360"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sfackler/rust-openssl/commit/f014afb230de4d77bc79dea60e7e58c2f47b60f2"
  }, {
    "type" : "WEB",
    "url" : "https://crates.io/crates/openssl"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/sfackler/rust-openssl"
  }, {
    "type" : "WEB",
    "url" : "https://lists.debian.org/debian-lts-announce/2025/02/msg00009.html"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2025-0004.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-416" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-02-03T17:56:46Z",
    "nvd_published_at" : "2025-02-03T18:15:43Z"
  }
}