Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9a3262e04cf1e4b…

MALICIOUS

PDF

97.1 KB Created: 2021-07-05 09:58:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c937e369c7fb24bdac4061c33ab910aa SHA-1: d7d9992dbfe2cfaa8b7c44642d3a1818a0119fc0 SHA-256: b9a3262e04cf1e4b64522a5e04ed1b713201c80c03f7301867ab6d4f2982d36c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised WordPress sites, which in turn host other PDF files. This structure suggests a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, with the URLs likely serving as a distribution mechanism for further stages or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d28bb7dbc---31293253311.pdf
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/ff3903ad770850be04546f2d62ae1c0a/60067511494.pdf
    • https://aartipalette.com/userfiles/file/67683515199.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/a9e00d95cddfc3a73f128dd4c73c2e29/nelow.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/a51i3g21ee3mv0lcc90gkb0a2r/41036319478.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d575ee34440---tabixubuwo.pdf
    • http://thegibbsfamilyreunion.com/clients/d/d9/d929505c7faf6263097cc97620c39d65/File/valemas.pdf
    • https://publicbridge.pl/userfiles/file/90328594528.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aacee8aa8f6---renuvusebifutir.pdf
    • https://jamurgoreng.net/contents//files/lijibavureruroruleweso.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160848fe3473cf---39079472514.pdf
    • http://jorkurojus.com/userfiles/file/3931781594.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/4han9a23apegmjckd762e5skl2/pezuvomimodisizedip.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/a9de7bbe8a73eafba06dfa1f04b52ecb/jatobixazexegopuxirora.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca041e85c26---82655965852.pdf
    • http://etcad.net/np/upfile/file/jabakiduzifikuxazo.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/56b13c59799489d6ca9b2408f1bfa357/pezofesepelubuga.pdf
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16241547060523.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e35688e9d8---38297691273.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/qlbna9e0nbdbvpn9bomd9vo0b2/75681110108.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608992f5a42fd---nufinepego.pdf
    • https://equantumconsulting.com/files/files/sagarudiwekawor.pdf
    • http://brilspa.ro/userfiles/file///85131196052.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/32e76b29d69211dc3ac67d2c6fe4c011/36746394595.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/90ac1966af506c804bdc1c177f3a7c9c/jinasotevokovaboxis.pdf
    • http://miroslaws.com/ckfinder/userfiles/files/30628489601.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=number+to+letter+chart
    • 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_off00010c7f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C7F 16792 bytes
font_01_sfnt_off00012496.bin
5fc2bb8192eb716f0723e8188fd9b0cee00f7b1bc389bafc89bcd1acc0ffcf29
pdf-font-stream PDF embedded font (sfnt) at offset 0x12496 10348 bytes
font_02_sfnt_off00013bf3.bin
201050f31255c53dd7fcf30fcf5d7d5fbef9de7ce135d4ce65b44e3341ecc975
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF3 26856 bytes