Malicious PDF — malware analysis report

Static analysis result for SHA-256 139a76c7150088e3…

MALICIOUS

PDF

83.3 KB Created: 2021-09-07 16:46:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 314cafc32a6ec320fdf66cf93188cd5d SHA-1: f6cd9ef85c51abe3f2d883f270a49cace5b83ca0 SHA-256: 139a76c7150088e309e58b9c4b5784c59344a684664c6c60b9d2fafa2b3daa48
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The presence of multiple distinct hosts and the use of 'utm_term' parameters indicate an attempt to obscure the final destination and potentially track user interactions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://smidgel.ru/uplcv?utm_term=charge+3+portable+wireless+speaker+manual
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/p4rdr3i4ct3vbv0gd059hkiu32/56210794212.pdf
    • http://rqconsultores.com/userfiles/file/fozogibelisezowufe.pdf
    • https://mkserwis.pl/userfiles/file/87752221178.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/bbb7de3c0e759a4917b8d8e26c8f8d2e/jopemikibiwatof.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/2d3e2d3d28a573f31a8193f2d6ed68dc/zarudigigunolex.pdf
    • http://clinton.abwingsmd.com/uploads/files/15467621104.pdf
    • http://renovfab-menuiserie.com/userfiles/file/71049709858.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16085deba72993---71475243299.pdf
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/a86649cc6f654339636afa09a564d7a8/449256561.pdf
    • http://snsi.jp/image/news_file/bolulazanejuxaniwezepis.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acafe0c2dce---57848435530.pdf
    • http://aisef.org/uploads/userfiles/file/file/60750307298.pdf
    • https://rajaketiga.com/contents//files/sewejejuzekebuv.pdf
    • https://jvlegacyhomerepairsmd.com/nbloom/fckuploads/file/37148463235.pdf
    • http://nomayaku.com/userfiles/file/17624693360.pdf
    • http://swissfun.tv/var/www/porn4me.ch/web/ckfinder/userfiles/files/59459413109.pdf
    • http://top1np.com/ckfinder/userfiles/files/71298580291.pdf
    • https://lemarko.com/userfiles/file/82245079600.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16089a6ad97545---potobonidodusumogekunis.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e82b5cb273---sonivisovufiwofep.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/bdf2ba4a997e7aa1b098c6fd1938d35e/semaleridavipavajiwi.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/5895fc124f1be0e749ab4c0083e384cf/tasifiz.pdf
    • http://adabaskimerkezi.com/upload/file/70968719221.pdf
    • https://underworldgear.com/upload/users/files/37906581560.pdf
    • https://surupaceanu.ro/ckfinder/userfiles/files/fixogoxuwawuxini.pdf
    • 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_off0000d53f.bin
dbd81ba8a490afb441ea3344c8e140e4dd591000dec51f8fe7f608c2c8f6c5bb
pdf-font-stream PDF embedded font (sfnt) at offset 0xD53F 11320 bytes
font_01_sfnt_off0000ef95.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF95 16792 bytes
font_02_sfnt_off000107a7.bin
81185a29fdd4ce92479d51f2f8a33443cc4d81049a57f0e5177ed0af7a43e0f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x107A7 21940 bytes