Malicious PDF — malware analysis report

Static analysis result for SHA-256 16b3f62c0a0c3026…

MALICIOUS

PDF

106.4 KB Created: 2021-07-02 10:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1aacda00fac6458d574d86c4038980a0 SHA-1: 974693d3f6626efcb09baa95b41476f76159a36e SHA-256: 16b3f62c0a0c3026d83edd00b4541b568f9059dd65af270ced96dc277b3f7c1f
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised CMS upload directories, suggesting it's designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm structure and heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ef02b5ddd---9379326517.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/9134d9f803e483b89e79a0d7e7acfb3c/6712549612.pdf
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/25c197ae5bd60cc8864d7c58750f5901/12594588289.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ffdf75584---tilefobevudogo.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608672cceaaba---92720805984.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/5aehd6dle13v530t5p78evvfrb/52642982185.pdf
    • https://epiphanych.com/images/file/xuruworezagagufexusanivo.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/14703a6d1ea484681519be607e285451/savubovesukiwatisediw.pdf
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/29030201212.pdf
    • http://kppzp.pl/userfiles/file/65345510901.pdf
    • http://highendschmiede.de/highendfiles/file/84516310108.pdf
    • http://thestarbusan.net/FileData/ckfinder/files/20210626_7A489B585E997E0F.pdf
    • http://palakkadtourism.in/ckfinder/userfiles/files/49884638523.pdf
    • https://a2designbg.com/userfiles/file/bifekudetuzixekobuko.pdf
    • https://arrayamed.com/userfiles/file/tasutefiga.pdf
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/6a9c1f61d7596793356382972d92fb27/sibuvaput.pdf
    • http://thementalhealthadvocates.org/files/userfiles/file/47615342614.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160760b4846d3b---10808637729.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091863b6e757---zaxeniboxunekojudasuzefi.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16071c901d5700---83226550134.pdf
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/2aacb860c040e5a4ea6b457b37b4a723/susupatajozel.pdf
    • http://goref.ru/files/file/58960414865.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607683b920292---mubonemamokovel.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=how+does+exercise+affect+the+cardiovascular+system
    • 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_off00013b80.bin
87bdcb6080b7fb54f2e9f34da968b99131bf616ecdfd86faf132c76a7c899c31
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B80 17756 bytes
font_01_sfnt_off00016a4e.bin
686f44fd0a1cdae03f436dc2969f1789a94e47b99d67aa196573c0b950e3ecca
pdf-font-stream PDF embedded font (sfnt) at offset 0x16A4E 11096 bytes
font_02_sfnt_off0001843d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1843D 16792 bytes