Malicious PDF — malware analysis report

Static analysis result for SHA-256 13a0616ec7b4b9a2…

MALICIOUS

PDF

71.9 KB Created: 2021-09-17 06:25:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2875536cd456dfa417227fe361739ef3 SHA-1: 685edc494191516f84ae30a904e4cf2aebc3a780 SHA-256: 13a0616ec7b4b9a20e294d8dcd581f5e8bc53f23c6912ba85be6a8ec9635422a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Additionally, multiple heuristics indicate the presence of link farms pointing to compromised WordPress upload directories, suggesting an attempt to host or distribute further malicious content. The ClamAV detection and ML classifier strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fecbdaabaf---55033070757.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16133e9641615c---50516701586.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/161340fe8a8266---goxubisiletukawir.pdf
    • http://cleversystems.ru/userfiles/file/79114340759.pdf
    • http://weifong.tw/fckimages/file/19403408284.pdf
    • https://permargi.com/files/galeria/files/migazolixoduvikatefedip.pdf
    • http://koreanhotpot.com/uploads/files/77039960965.pdf
    • https://novsport.com/content/File/2156697876.pdf
    • https://harteron.ee/userfiles/file/kiwabigizolafepimowefaxe.pdf
    • https://promaxsuspension.com/csmimage/file/59201717485.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/84c65eb981f5e71beeafc00389522864/rugarofifedax.pdf
    • http://krr-nfe.com/suratnfe/UserFiles/File/dikutapiselopalo.pdf
    • https://bruceleevideos.org/images/file/45670190786.pdf
    • http://everbeenmagnet.com/js/upfiles/files/pilevakogoz.pdf
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59270793770.pdf
    • http://sineadstone.com/userfiles/file/kuforenimow.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0c6a7e75c---zuzitipixuxenifudobaxew.pdf
    • http://noospc.ru/SITE/files/editor/file/vuwovimosad.pdf
    • http://hatdesechia.com/storage/ckfinder/files/84824946732.pdf
    • http://flexinform.com/hirlevel/file/72065341130.pdf
    • http://gamjagolla.com/uploads/files/86379953625.pdf
    • http://medicalproduct.hu/images/files/40416382070.pdf
    • http://mbjarrahi.com/UploadedFiles/New/file/62909215149.pdf
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/3211126085.pdf
    • https://behbehaniprojects.com/uploads/files/losoti.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=idm+download+latest+version+2021
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b403.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB403 16792 bytes
font_01_sfnt_off0000cc1a.bin
63d30b33fc917f8bdcaaa5c6f3b741ecf5c1d4e2db0f06e8060bd23816d5216f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1A 10804 bytes
font_02_sfnt_off0000e51c.bin
61035a9d952cfc598cb29647b0169147a3260c59e84653dbc726f92ac2fe9abc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE51C 17452 bytes