What is CVE-2023-34457?

MechanicalSoup is a Python library for automating interaction with websites. Starting in version 0.2.0 and prior to version 1.3.0, a malicious web server can read arbitrary files on the client using a ` ` inside HTML form. All users of MechanicalSoup's form submission are affected, unless they took very specific (and manual) steps to reset HTML form field values. Version 1.3.0 contains a patch for this issue.

How severe is CVE-2023-34457?

CVE-2023-34457 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-34457 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-34457?

CVE-2023-34457 affects Mechanicalsoup Project Mechanicalsoup. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-34457?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-34457 published?

CVE-2023-34457 was published on 2023-07-05 and last updated on 2026-06-17.

CVE-2023-34457

CVE-2023-34457 is a medium-severity vulnerability in Mechanicalsoup Project Mechanicalsoup with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mechanicalsoup Project Mechanicalsoup
Published: 2023-07-05
Last modified: 2026-06-17

Description

MechanicalSoup is a Python library for automating interaction with websites. Starting in version 0.2.0 and prior to version 1.3.0, a malicious web server can read arbitrary files on the client using a `<input type="file" ...>` inside HTML form. All users of MechanicalSoup's form submission are affected, unless they took very specific (and manual) steps to reset HTML form field values. Version 1.3.0 contains a patch for this issue.

Frequently asked questions

What is CVE-2023-34457?: MechanicalSoup is a Python library for automating interaction with websites. Starting in version 0.2.0 and prior to version 1.3.0, a malicious web server can read arbitrary files on the client using a `<input type="file" ...>` inside HTML form. All users of MechanicalSoup's form submission are affected, unless they took very specific (and manual) steps to reset HTML form field values. Version 1.3.0 contains a patch for this issue.
How severe is CVE-2023-34457?: CVE-2023-34457 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-34457 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-34457?: CVE-2023-34457 affects Mechanicalsoup Project Mechanicalsoup. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-34457?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-34457 published?: CVE-2023-34457 was published on 2023-07-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mechanicalsoup_project:mechanicalsoup:*:*:*:*:*:python:*:*

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