{"id":"CVE-2024-47174","aliases":["DEBIAN-CVE-2024-47174","EUVD-2024-42296","GHSA-6fjr-mq49-mm2c","UBUNTU-CVE-2024-47174","USN-7633-1"],"status":"published","title":"Credential leak when credentials are used with `\u003cnix/fetchurl.nix\u003e`","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","severity":{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00297,"percentile":0.2265,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-287"],"published":"2024-09-26T17:27:53Z","modified":"2026-11-02T12:02:51Z","fixes":[{"ecosystem":"Debian:13","package":"nix","fixed_in":["2.24.8+dfsg-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"nix","fixed_in":["2.24.8+dfsg-1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nix","fixed_in":["2.6.0+dfsg-3ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nix","fixed_in":["2.18.1+dfsg-1ubuntu5+esm2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.1+dfsg-1","2.16.1+dfsg-2","2.16.1+dfsg-3","2.17.1+dfsg-1","2.18.1+dfsg-1","2.22.1+dfsg-1","2.23.3+dfsg-1","2.23.3+dfsg-2","2.24.12+dfsg-1","2.24.8+dfsg-1","2.24.9+dfsg-1","2.24.9+dfsg-2","2.25.4+dfsg-1","2.26.3+dfsg-1","2.32.5+dfsg-1","2.32.5+dfsg-2","2.34.3+dfsg-1","2.34.6+dfsg-1","2.34.8+dfsg-1","2.35.4+dfsg-1","2.8.0-1.1"]},{"source":"osv","ecosystem":"Debian:13","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.24.8+dfsg-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.24.8+dfsg-1"}]}]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.6.0+dfsg-3ubuntu0.1~esm1"}]}],"versions":["2.3.10+dfsg1-1","2.3.10+dfsg1-1build1","2.6.0+dfsg-2","2.6.0+dfsg-3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.18.1+dfsg-1ubuntu5+esm2"}]}],"versions":["2.16.1+dfsg-3ubuntu1","2.18.1+dfsg-1ubuntu1","2.18.1+dfsg-1ubuntu2","2.18.1+dfsg-1ubuntu4","2.18.1+dfsg-1ubuntu5"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.6.0+dfsg-3ubuntu0.1~esm1"}]}],"versions":["2.3.10+dfsg1-1","2.3.10+dfsg1-1build1","2.6.0+dfsg-2","2.6.0+dfsg-3"],"bundled":4},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nix","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.18.1+dfsg-1ubuntu5+esm2"}]}],"versions":["2.16.1+dfsg-3ubuntu1","2.18.1+dfsg-1ubuntu1","2.18.1+dfsg-1ubuntu2","2.18.1+dfsg-1ubuntu4","2.18.1+dfsg-1ubuntu5"],"bundled":4}],"products":[{"vendor":"nixos","product":"nix"}],"references":[{"url":"https://github.com/NixOS/nix/security/advisories/GHSA-6fjr-mq49-mm2c","tags":["x_refsource_CONFIRM","advisory","report"]},{"url":"https://github.com/NixOS/nix/pull/11585","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/NixOS/nix/commit/062b4a489e30da9c85fa4ff15cfdd2e51cac7b90","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/NixOS/nix/commit/5db358d4d78aea7204a8f22c5bf2a309267ee038","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/47xxx/CVE-2024-47174.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2024-47174","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2024-47174","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2024-47174","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2024-47174","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-7633-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2024-27297","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2024-38531","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2024-45593","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2024-47174","title":"Credential leak when credentials are used with `\u003cnix/fetchurl.nix\u003e`","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T17:27:53.966Z","modified":"2024-09-26T17:49:28.342Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:33:57.302325Z"}],"euvd":[{"id":"EUVD-2024-42296","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T17:27:53Z","modified":"2024-09-26T17:49:28Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-03T00:28:08.503734Z"}],"nvd":[{"id":"CVE-2024-47174","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T18:15:10.84Z","modified":"2026-06-17T07:56:40.453Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:10:29.044588Z"}],"osv":[{"id":"CVE-2024-47174","title":"Credential leak when credentials are used with `\u003cnix/fetchurl.nix\u003e`","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T17:27:53.966Z","modified":"2026-10-28T10:58:22.309985716Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T15:44:43.253252Z"},{"id":"DEBIAN-CVE-2024-47174","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote  store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T18:15:10.84Z","modified":"2026-11-02T12:02:51.63467147Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:43.798789Z"},{"id":"UBUNTU-CVE-2024-47174","description":"Nix is a package manager for Linux and other Unix systems. Starting in version 1.11 and prior to versions 2.18.8 and 2.24.8, `\u003cnix/fetchurl.nix\u003e` did not verify TLS certificates on HTTPS connections. This could lead to connection details such as full URLs or credentials leaking in case of a man-in-the-middle (MITM) attack. `\u003cnix/fetchurl.nix\u003e` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue. A user may be affected by the risk of leaking credentials if they have a `netrc` file for authentication, or rely on derivations with `impureEnvVars` set to use credentials from the environment. In addition, the commonplace trust-on-first-use (TOFU) technique of updating dependencies by specifying an invalid hash and obtaining it from a remote store was also vulnerable to a MITM injecting arbitrary store objects. This also applied to the impure derivations experimental feature. Note that this may also happen when using Nixpkgs fetchers to obtain new hashes when not using the fake hash method, although that mechanism is not implemented in Nix itself but rather in Nixpkgs using a fixed-output derivation. The behavior was introduced in version 1.11 to make it consistent with the Nixpkgs `pkgs.fetchurl` and to make `\u003cnix/fetchurl.nix\u003e` work in the derivation builder sandbox, which back then did not have access to the CA bundles by default. Nowadays, CA bundles are bind-mounted on Linux. This issue has been fixed in Nix 2.18.8 and 2.24.8. As a workaround, implement (authenticated) fetching with `pkgs.fetchurl` from Nixpkgs, using `impureEnvVars` and `curlOpts` as needed.","status":"published","published":"2024-09-26T18:15:00Z","modified":"2026-02-04T03:28:08.725443Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T16:55:02.636559Z"},{"id":"USN-7633-1","title":"nix vulnerabilities","description":"Linus Heckemann discovered that Nix did not correctly handle certain\nbinaries. An attacker could possibly use this issue to execute\narbitrary code. (CVE-2024-38531)\n\nPierre-Etienne Meunier discovered that Nix did not correctly handle TLS\ncertificates. A remote attacker could possibly use this issue to leak\nsensitive information. (CVE-2024-47174)\n\nIt was discovered that Nix did not correctly handle Unix sockets. An\nattacker could possibly use this issue execute arbitrary code. This issue\nonly affected Ubuntu 24.04 LTS. (CVE-2024-27297)\n\nIt was discovered that Nix did not correctly handle unpacking Nix\narchives (NARS). If a user or automated system were tricked into opening\na specially crafted file, an attacker could possibly use this issue to\ncause a denial of service or execute arbitrary code. (CVE-2024-45593)","status":"published","published":"2025-07-14T00:19:28Z","modified":"2026-04-27T18:08:59.766995Z","updated_at":"2026-11-02T16:58:19.988474Z"}]}}