Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b130b37ab3b50a…

MALICIOUS

PDF

89.2 KB Created: 2021-07-10 05:32:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4b30889de2d8d5f7f4bd795534191712 SHA-1: 8764cfca68af68b30b46206a322e799f86e1836a SHA-256: 81b130b37ab3b50a72da55be6067b7ddfc5a3b03fdcf0de03e52765569344038
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a tactic for SEO poisoning or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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 http://pogotowienaukowe.com/Upload/file/xoguzakejebot.pdf
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8372c9910---41636040914.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb9512871e6---71321748444.pdf
    • https://cargobull.cz/res/file/lufisapefemexelupizaz.pdf
    • http://ash-graphy.com/userfiles/file/jusub.pdf
    • http://vogiantinhmach.com/media/ftp/file/dotogenifapozojamawu.pdf
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/ffc64559bfc8fc5a96155833a02cbc65/19463778431.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/5aclvi4f011bkmg7h0fp1uv182/47047946364.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a772e1bbd44---zojadusulaxenovij.pdf
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/448d1597c28f2cddfceeeb89ede15cb5/57582192361.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/v66p9j3ajagk8i5b00foo1ike7/45191430473.pdf
    • http://wwstationery.com/files/file/22489243714.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c928368925a---tubenazazosegunolago.pdf
    • http://bezpiecznamlodosc.org/files/file/40145597742.pdf
    • http://agapetown.net/ckfinder/userfiles/files/64047386737.pdf
    • http://neonyazilim.com/images/Media/files/32163487096.pdf
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/2597268923.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/7c006b04a6de3cd39e0cde6f04240db3/37812858217.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cf4c4b9e620---59903726617.pdf
    • https://preciseenergygroup.com/media/zagasuxutegaxip.pdf
    • https://strechybenesov.cz/content/72636837354.pdf
    • https://privatecambodiatour.com/userfiles/file/20910202096.pdf
    • http://24cvety.ru/upload/files/momav.pdf
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/eae5521f8c3748f51da6db615366d47c/58580370010.pdf
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/5d417d7617216edb356cd9e8fab7bb8d/maderubizixivexeborodap.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=sesame+street+let%27s+eat+funny+food+songs+1999+vhs
    • 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
font_00_sfnt_off0000ef88.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF88 16792 bytes
font_01_sfnt_off0001079a.bin
caeb73d5368d77ca126d437defff5796fefaac755b0c48b425c2ee47d6c3bfe0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1079A 17280 bytes
font_02_sfnt_off000133e2.bin
bb6bae6cb71e369e4daf95c9662711c92bb8c7cdb295eb4807ffd1f6a24ce4bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x133E2 1708 bytes
font_03_sfnt_off00013c0a.bin
f7ccb815b7bb388ede88c2c3b5aa6a63068003bde8e6c721947ddc00e5eca633
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C0A 11320 bytes