Malicious PDF — malware analysis report

Static analysis result for SHA-256 316d64543ad17aa5…

MALICIOUS

PDF

79.2 KB Created: 2021-06-01 18:51:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 77f0728bd8f323d3d6fff8e9acf6fed4 SHA-1: 5cac9ecdc24e3e2a732026248d698f1495e1bf2c SHA-256: 316d64543ad17aa51faf265846cf750a828996cf1789d1a5f8c7219c9bd4ee1a
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, appears to be a lure related to technical specifications, likely to trick users into clicking the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://immobilieninvestors.eu/userfiles/file/65080457838.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/fd281bdf8faef0e66ca8028ef34632a9/61892912805.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d28d14b04e---66763056994.pdf
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/676e1c2430bdc2a320dcc0bb9aaf6d3d/gatosar.pdf
    • http://alarcon-v.com/editor_upload_image/file/fopadawogivamup.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/0721c667c85ab7c978db9ae69b8c0574/14385304274.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160833a949de91---manudisipum.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/3a70c6dee1547471b53bb64d69d3cbfe/76057332485.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d0ce81cd4---fikozonomikidakeb.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160accc538d349---dozogafojuxekekeve.pdf
    • http://paynechapelduquesne.org/clients/9/9b/9b910c66cef3ae2d1bb1fd5804160a19/File/lisoxuxagatiwuzuvilomebe.pdf
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/0mk01op5h8l6ko9h1nh27il898/39552347691.pdf
    • https://pima-alarms.net/slicice/file/tisojinin.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0013e4f0a---23288424720.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160899bd2a92fc---61604757388.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/bkc4tklaecq16khclnmaa9eek2/sosotibejamemotovejalu.pdf
    • http://luingpyrex.cz/foto/Image/file/4188732648.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/1mh0dhggmoli2s2ntcd5s34d9m/noteforakusuj.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=how+many+watts+can+a+kicker+comp+15+handle
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7a8.bin
095fb87d2e5f67df014abaa71a0b05fd6d8a19eb2c53cb1dd2c5d109eab35a62
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A8 5708 bytes
font_01_sfnt_off00010b0b.bin
83c70c324bbc8aa4ad820b11268c304dbdbf824bf9ee14ce4bc92ca5ed8ccc36
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0B 11088 bytes