CVE-2026-40087
CVE-2026-40087 · LangChain has incomplete f-string validation in prompt templates
Cette page présente des faits issus de sources publiques. Consultez l’avis original avant toute mise à jour.
LangChain is a framework for building agents and LLM-powered applications. Prior to 0.3.84 and 1.2.28, LangChain's f-string prompt-template validation was incomplete in two respects. First, some prompt template classes accepted f-string templates and formatted them without enforcing the same attribute-access validation as PromptTemplate. In particular, DictPromptTemplate and ImagePromptTemplate could accept templates containing attribute access or indexing expressions and subsequently evaluate those expressions during formatting. Second, f-string validation based on parsed top-level field names did not reject nested replacement fields inside format specifiers. In this pattern, the nested replacement field appears in the format specifier rather than in the top-level field name. As a result, earlier validation based on parsed field names did not reject the template even though Python formatting would still attempt to resolve the nested expression at runtime. This vulnerability is fixed in 0.3.84 and 1.2.28.
CVSS 5.3 · Moyenne · EPSS 0,3% · Correctif disponible
- Publication
- Mise à jour
Pile logicielle: python
Produits et versions concernés
langchain
- Versions du logiciel
- < 0.3.83: Concernée
- >= 1.0.0a1, < 1.2.28: Concernée
Aucun correctif publié
langchain-core PyPI
- Versions du logiciel
- 0.0.1
- 0.0.10
- 0.0.11
- 0.0.12
- 0.0.13
- 0.0.13rc1
- 0.0.13rc2
- 0.0.2
- 0.0.3
- 0.0.4
- 0.0.5
- 0.0.6
- 0.0.7
- 0.0.8
- 0.0.9
- 0.1.0
- 0.1.1
- 0.1.10
- 0.1.11
- 0.1.12
- 0.1.12rc1
- 0.1.13
- 0.1.14
- 0.1.15
- 0.1.15rc1
- 0.1.15rc2
- 0.1.16
- 0.1.17
- 0.1.18
- 0.1.19
- 0.1.2
- 0.1.20
- 0.1.21
- 0.1.22
- 0.1.23
- 0.1.24
- 0.1.25
- 0.1.26
- 0.1.27
- 0.1.28
- 0.1.29
- 0.1.3
- 0.1.30
- 0.1.31
- 0.1.32
- 0.1.33
- 0.1.33rc1
- 0.1.34
- 0.1.35
- 0.1.36
- 0.1.37
- 0.1.38
- 0.1.39
- 0.1.4
- 0.1.40
- 0.1.41
- 0.1.42
- 0.1.42rc1
- 0.1.43
- 0.1.44
- 0.1.45
- 0.1.46
- 0.1.47
- 0.1.47rc1
- 0.1.48
- 0.1.49
- 0.1.5
- 0.1.50
- 0.1.51
- 0.1.52
- 0.1.53
- 0.1.6
- 0.1.7
- 0.1.8
- 0.1.9
- 0.2.0
- 0.2.0rc1
- 0.2.1
- 0.2.10
- 0.2.11
- 0.2.12
- 0.2.13
- 0.2.15
- 0.2.16
- 0.2.17
- 0.2.18
- 0.2.19
- 0.2.2
- 0.2.20
- 0.2.21
- 0.2.22
- 0.2.23
- 0.2.24
- 0.2.25
- 0.2.26
- 0.2.27
- 0.2.28
- 0.2.29
- 0.2.29rc1
- 0.2.2rc1
- 0.2.3
- 0.2.30
- 0.2.31
- 0.2.32
- 0.2.33
- 0.2.34
- 0.2.35
- 0.2.36
- 0.2.37
- 0.2.38
- 0.2.39
- 0.2.4
- 0.2.40
- 0.2.41
- 0.2.42
- 0.2.43
- 0.2.5
- 0.2.6
- 0.2.7
- 0.2.8
- 0.2.9
- 0.3.0
- 0.3.0.dev0
- 0.3.0.dev1
- 0.3.0.dev2
- 0.3.0.dev3
- 0.3.0.dev4
- 0.3.0.dev5
- 0.3.1
- 0.3.10
- 0.3.11
- 0.3.12
- 0.3.13
- 0.3.14
- 0.3.15
- 0.3.16
- 0.3.17
- 0.3.18
- 0.3.19
- 0.3.2
- 0.3.20
- 0.3.21
- 0.3.22
- 0.3.23
- 0.3.24
- 0.3.25
- 0.3.26
- 0.3.27
- 0.3.28
- 0.3.29
- 0.3.3
- 0.3.30
- 0.3.31
- 0.3.32
- 0.3.33
- 0.3.34
- 0.3.34rc1
- 0.3.34rc2
- 0.3.35
- 0.3.36
- 0.3.37
- 0.3.38
- 0.3.39
- 0.3.4
- 0.3.40
- 0.3.41
- 0.3.42
- 0.3.43
- 0.3.44
- 0.3.45
- 0.3.45rc1
- 0.3.46
- 0.3.47
- 0.3.48
- 0.3.49
- 0.3.5
- 0.3.50
- 0.3.51
- 0.3.52
- 0.3.53
- 0.3.54
- 0.3.55
- 0.3.56
- 0.3.56rc1
- 0.3.57
- 0.3.58
- 0.3.59
- 0.3.6
- 0.3.60
- 0.3.61
- 0.3.62
- 0.3.63
- 0.3.64
- 0.3.65
- 0.3.66
- 0.3.67
- 0.3.68
- 0.3.69
- 0.3.7
- 0.3.70
- 0.3.71
- 0.3.72
- 0.3.73
- 0.3.74
- 0.3.75
- 0.3.76
- 0.3.77
- 0.3.78
- 0.3.79
- 0.3.8
- 0.3.80
- 0.3.81
- 0.3.82
- 0.3.83
- 0.3.9
- Plages de versions concernées
- ECOSYSTEM: < 0.3.84
Mettez à jour vers 0.3.84
langchain-core PyPI
- Versions du logiciel
- 1.0.0
- 1.0.0a1
- 1.0.0a2
- 1.0.0a3
- 1.0.0a4
- 1.0.0a5
- 1.0.0a6
- 1.0.0a7
- 1.0.0a8
- 1.0.0rc1
- 1.0.0rc2
- 1.0.0rc3
- 1.0.1
- 1.0.2
- 1.0.3
- 1.0.4
- 1.0.5
- 1.0.6
- 1.0.7
- 1.1.0
- 1.1.1
- 1.1.2
- 1.1.3
- 1.2.0
- 1.2.1
- 1.2.10
- 1.2.11
- 1.2.12
- 1.2.13
- 1.2.14
- 1.2.15
- 1.2.16
- 1.2.17
- 1.2.18
- 1.2.19
- 1.2.2
- 1.2.20
- 1.2.21
- 1.2.22
- 1.2.23
- 1.2.24
- 1.2.25
- 1.2.26
- 1.2.27
- 1.2.3
- 1.2.4
- 1.2.5
- 1.2.6
- 1.2.7
- 1.2.8
- 1.2.9
- Plages de versions concernées
- ECOSYSTEM: ≥ 1.0.0a1, < 1.2.28
Mettez à jour vers 1.2.28
langchain-core PyPI
- Versions du logiciel
- 0.0.1
- 0.0.10
- 0.0.11
- 0.0.12
- 0.0.13
- 0.0.13rc1
- 0.0.13rc2
- 0.0.2
- 0.0.3
- 0.0.4
- 0.0.5
- 0.0.6
- 0.0.7
- 0.0.8
- 0.0.9
- 0.1.0
- 0.1.1
- 0.1.10
- 0.1.11
- 0.1.12
- 0.1.12rc1
- 0.1.13
- 0.1.14
- 0.1.15
- 0.1.15rc1
- 0.1.15rc2
- 0.1.16
- 0.1.17
- 0.1.18
- 0.1.19
- 0.1.2
- 0.1.20
- 0.1.21
- 0.1.22
- 0.1.23
- 0.1.24
- 0.1.25
- 0.1.26
- 0.1.27
- 0.1.28
- 0.1.29
- 0.1.3
- 0.1.30
- 0.1.31
- 0.1.32
- 0.1.33
- 0.1.33rc1
- 0.1.34
- 0.1.35
- 0.1.36
- 0.1.37
- 0.1.38
- 0.1.39
- 0.1.4
- 0.1.40
- 0.1.41
- 0.1.42
- 0.1.42rc1
- 0.1.43
- 0.1.44
- 0.1.45
- 0.1.46
- 0.1.47
- 0.1.47rc1
- 0.1.48
- 0.1.49
- 0.1.5
- 0.1.50
- 0.1.51
- 0.1.52
- 0.1.53
- 0.1.6
- 0.1.7
- 0.1.8
- 0.1.9
- 0.2.0
- 0.2.0rc1
- 0.2.1
- 0.2.10
- 0.2.11
- 0.2.12
- 0.2.13
- 0.2.15
- 0.2.16
- 0.2.17
- 0.2.18
- 0.2.19
- 0.2.2
- 0.2.20
- 0.2.21
- 0.2.22
- 0.2.23
- 0.2.24
- 0.2.25
- 0.2.26
- 0.2.27
- 0.2.28
- 0.2.29
- 0.2.29rc1
- 0.2.2rc1
- 0.2.3
- 0.2.30
- 0.2.31
- 0.2.32
- 0.2.33
- 0.2.34
- 0.2.35
- 0.2.36
- 0.2.37
- 0.2.38
- 0.2.39
- 0.2.4
- 0.2.40
- 0.2.41
- 0.2.42
- 0.2.43
- 0.2.5
- 0.2.6
- 0.2.7
- 0.2.8
- 0.2.9
- 0.3.0
- 0.3.0.dev0
- 0.3.0.dev1
- 0.3.0.dev2
- 0.3.0.dev3
- 0.3.0.dev4
- 0.3.0.dev5
- 0.3.1
- 0.3.10
- 0.3.11
- 0.3.12
- 0.3.13
- 0.3.14
- 0.3.15
- 0.3.16
- 0.3.17
- 0.3.18
- 0.3.19
- 0.3.2
- 0.3.20
- 0.3.21
- 0.3.22
- 0.3.23
- 0.3.24
- 0.3.25
- 0.3.26
- 0.3.27
- 0.3.28
- 0.3.29
- 0.3.3
- 0.3.30
- 0.3.31
- 0.3.32
- 0.3.33
- 0.3.34
- 0.3.34rc1
- 0.3.34rc2
- 0.3.35
- 0.3.36
- 0.3.37
- 0.3.38
- 0.3.39
- 0.3.4
- 0.3.40
- 0.3.41
- 0.3.42
- 0.3.43
- 0.3.44
- 0.3.45
- 0.3.45rc1
- 0.3.46
- 0.3.47
- 0.3.48
- 0.3.49
- 0.3.5
- 0.3.50
- 0.3.51
- 0.3.52
- 0.3.53
- 0.3.54
- 0.3.55
- 0.3.56
- 0.3.56rc1
- 0.3.57
- 0.3.58
- 0.3.59
- 0.3.6
- 0.3.60
- 0.3.61
- 0.3.62
- 0.3.63
- 0.3.64
- 0.3.65
- 0.3.66
- 0.3.67
- 0.3.68
- 0.3.69
- 0.3.7
- 0.3.70
- 0.3.71
- 0.3.72
- 0.3.73
- 0.3.74
- 0.3.75
- 0.3.76
- 0.3.77
- 0.3.78
- 0.3.79
- 0.3.8
- 0.3.80
- 0.3.81
- 0.3.82
- 0.3.83
- 0.3.9
- 1.0.0
- 1.0.0a1
- 1.0.0a2
- 1.0.0a3
- 1.0.0a4
- 1.0.0a5
- 1.0.0a6
- 1.0.0a7
- 1.0.0a8
- 1.0.0rc1
- 1.0.0rc2
- 1.0.0rc3
- 1.0.1
- 1.0.2
- 1.0.3
- 1.0.4
- 1.0.5
- 1.0.6
- 1.0.7
- 1.1.0
- 1.1.1
- 1.1.2
- 1.1.3
- 1.2.0
- 1.2.1
- 1.2.10
- 1.2.11
- 1.2.12
- 1.2.13
- 1.2.14
- 1.2.15
- 1.2.16
- 1.2.17
- 1.2.18
- 1.2.19
- 1.2.2
- 1.2.20
- 1.2.21
- 1.2.22
- 1.2.23
- 1.2.24
- 1.2.25
- 1.2.26
- 1.2.27
- 1.2.3
- 1.2.4
- 1.2.5
- 1.2.6
- 1.2.7
- 1.2.8
- 1.2.9
- Plages de versions concernées
- ECOSYSTEM: < 0.3.84 ∪ ≥ 1.0.0a1, < 1.2.28
Mettez à jour vers 0.3.84; Mettez à jour vers 1.2.28
Sources originales
- https://github.com/langchain-ai/langchain/security/advisories/GHSA-926x-3r5x-gfhw
- https://github.com/langchain-ai/langchain/pull/36612
- https://github.com/langchain-ai/langchain/pull/36613
- https://github.com/langchain-ai/langchain/commit/6bab0ba3c12328008ddca3e0d54ff5a6151cd27b
- https://github.com/langchain-ai/langchain/commit/af2ed47c6f008cdd551f3c0d87db3774c8dfe258
- https://github.com/langchain-ai/langchain/releases/tag/langchain-core%3D%3D0.3.84
- https://github.com/langchain-ai/langchain/releases/tag/langchain-core%3D%3D1.2.28
- https://nvd.nist.gov/vuln/detail/CVE-2026-40087