python-flask: Denial of Service via crafted JSON file
Published Aug 20, 2018
8.7
HIGHCVSS 4.0
EPSS 3.85%
Description
The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.
Affected products
No data.
Configuration 1
- < 0.12.3
Configuration 2
- n/a
- n/a
- n/a
No data.
Red Hat Enterprise Linux 7 Extras
python-flask-1:0.10.1-5.el7_7
Fixed · RHSA-2020:0870
Red Hat Ceph Storage 2
python-flask
Affected
Red Hat Ceph Storage 3
python-flask
Fix deferred
Red Hat Ceph Storage 7
python-flask
Not affected
Red Hat Enterprise Linux 8
python-flask
Not affected
Red Hat Satellite 6
python-flask
Not affected
Red Hat Storage 3
python-flask
Fix deferred
Red Hat Update Infrastructure 3 for Cloud Providers
python-flask
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 Extras | python-flask-1:0.10.1-5.el7_7 | Fixed | RHSA-2020:0870 |
| Red Hat Ceph Storage 2 | python-flask | Affected | n/a |
| Red Hat Ceph Storage 3 | python-flask | Fix deferred | n/a |
| Red Hat Ceph Storage 7 | python-flask | Not affected | n/a |
| Red Hat Enterprise Linux 8 | python-flask | Not affected | n/a |
| Red Hat Satellite 6 | python-flask | Not affected | n/a |
| Red Hat Storage 3 | python-flask | Fix deferred | n/a |
| Red Hat Update Infrastructure 3 for Cloud Providers | python-flask | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the versions of python-flask as shipped with Red Hat Enterprise Linux 7. Although Red Hat Satellite 6 contains the vulnerable component, the former is not affected due to python-flask only receiving JSON data created by other Red Hat Satellite 6 components, not user-controlled JSON data, which makes the attack unfeasible.
Metrics
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (20 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 3.85% (0.03855) | 89.83th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.85% (0.03855) | 88.76th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.57% (0.00567) | 65.90th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.09% (0.02094) | 73.38th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.57% (0.00567) | 66.56th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.37% (0.00370) | 73.46th | v3 (v2023.03.01) |
| Jun 4, 2024 | 0.37% (0.00370) | 72.59th | v3 (v2023.03.01) |
| Apr 8, 2024 | 0.26% (0.00261) | 65.30th | v3 (v2023.03.01) |
| Feb 9, 2024 | 0.25% (0.00252) | 64.16th | v3 (v2023.03.01) |
| Aug 14, 2023 | 0.25% (0.00250) | 62.16th | v3 (v2023.03.01) |
| Jul 8, 2023 | 0.18% (0.00184) | 54.58th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.26% (0.00262) | 62.08th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.02% (0.01018) | 38.88th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.02% (0.01018) | 36.86th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.55% (0.01550) | 33.66th | v1 |
| Jan 6, 2022 | 1.55% (0.01550) | 32.96th | v1 |
| Sep 1, 2021 | 1.55% (0.01550) | 73.01th | v1 |
| Apr 14, 2021 | 1.55% (0.01550) | 0.00th | v1 |
References (12)
- https://access.redhat.com/security/cve/CVE-2018-1000656 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1623131 Issue Tracking
- https://github.com/advisories/GHSA-562c-5r94-xh97 Advisory
- https://github.com/pallets/flask/commit/b178e89e4456e777b1a7ac6d7199052d0dfdbbbe
- https://github.com/pallets/flask/pull/2691 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://github.com/pallets/flask/releases/tag/0.12.3 x_refsource_CONFIRMThird Party Advisory
- https://github.com/pypa/advisory-database/tree/main/vulns/flask/PYSEC-2018-66.yaml
- https://lists.debian.org/debian-lts-announce/2019/08/msg00025.html mailing-listx_refsource_MLIST
- https://nvd.nist.gov/vuln/detail/CVE-2018-1000656
- https://security.netapp.com/advisory/ntap-20190221-0001 x_refsource_CONFIRMPatchThird Party Advisory
- https://usn.ubuntu.com/4378-1 vendor-advisoryx_refsource_UBUNTU
- https://www.cve.org/CVERecord?id=CVE-2018-1000656
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2018-1000656 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1623131 | Issue Tracking | |
| https://github.com/advisories/GHSA-562c-5r94-xh97 | Advisory | |
| https://github.com/pallets/flask/commit/b178e89e4456e777b1a7ac6d7199052d0dfdbbbe | ||
| https://github.com/pallets/flask/pull/2691 | x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory | |
| https://github.com/pallets/flask/releases/tag/0.12.3 | x_refsource_CONFIRMThird Party Advisory | |
| https://github.com/pypa/advisory-database/tree/main/vulns/flask/PYSEC-2018-66.yaml | ||
| https://lists.debian.org/debian-lts-announce/2019/08/msg00025.html | mailing-listx_refsource_MLIST | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-1000656 | ||
| https://security.netapp.com/advisory/ntap-20190221-0001 | x_refsource_CONFIRMPatchThird Party Advisory | |
| https://usn.ubuntu.com/4378-1 | vendor-advisoryx_refsource_UBUNTU | |
| https://www.cve.org/CVERecord?id=CVE-2018-1000656 |
Change history (0)
No recorded changes yet.