Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c9f36f0f266863…

MALICIOUS

PDF

108.3 KB Created: 2021-07-05 17:19:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d60254ad6767930677f056bb5161650 SHA-1: 13d74c52be8488cf1ef5cdbd57383a9d5650acee SHA-256: 28c9f36f0f266863361f73237c7974dde3690b832d0b73fe109546b543836a99
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns are consistent with malicious PDF lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9882

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16096fdd4c6e80---xisewekuzero.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160b068f20528e---55213077011.pdf
    • http://bienchidan.org/uploads/files/nilizusodilekiwodu.pdf
    • http://gianniarnaudo.com/userfiles/files/remitet.pdf
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a562d30bdda---88454187044.pdf
    • https://cakenepal.com/userfiles/file/29715086338.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa6b5e5e71e---soxokaja.pdf
    • https://aprilboya.com/userfiles/file/dadomuge.pdf
    • https://guineaservicesproviders.com/gsp/files/14909133737.pdf
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609903e342200---dekawolojatadexakesor.pdf
    • https://techson-cctv.com/upload/file/59054585384.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb83e4201e---bafalomobo.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b38b930dde6---82845920543.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/8787a0c18dbb7b381afe574735b9241c/romobafewetetafuzutim.pdf
    • https://celebicatering.com/upload/ckfinder/files/safideledomubudutedovixom.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c00f7678df0r41c1052fsdlgr3/xofatifotadazev.pdf
    • http://www.abcklima.hu//data/editorfile/nezubej.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16096772199814---27971620774.pdf
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/b1c0854beba0c9e7c79705884e8bacdd/65596094489.pdf
    • https://hojoairport.com/images/file/bewubugamenujidoniko.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e099a7d2b6---27326586546.pdf
    • http://asfalon.com/__files/file/tipagovudafebabiru.pdf
    • http://xtra360.net/campannas/file/56033230932.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=meaning+of+profound+gratitude
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00011d5a.bin
4705410e5cd16cbb137d723597c15d431d82a1a3502e852071d9da146fd63cbf
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11D5A 21564 bytes
font_01_sfnt_off0001421f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1421F 16792 bytes
font_02_sfnt_off00015a31.bin
f1ffda1e712ef27a488c55c15428bd48d3445b2a7adbd5a0bc4a381265ac9cc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x15A31 18980 bytes
font_03_sfnt_off00018b6c.bin
18e91c69efbac00950005d8113ed1d1ef96909082d1dfa177b52d3a09a1499a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x18B6C 10552 bytes