Malicious PDF — malware analysis report

Static analysis result for SHA-256 26d0853b96df1037…

MALICIOUS

PDF

94.4 KB Created: 2021-09-09 08:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 77d10bb7b1445bfe740558e17c8076d4 SHA-1: 1609a532577de3f0cb5c41023a082f77a257bcff SHA-256: 26d0853b96df1037b367dc6d4b92f1c22e2458dd9eaa964cc3683f5a6c411f97
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it's a link farm. The embedded URLs point to various PDF files hosted on external domains, some of which appear to be compromised CMS uploads. The primary purpose seems to be redirecting users to potentially malicious content, possibly for phishing or SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://lighthousemacau.com/html_upload/file/jimuvozurinukezilanobodew.pdf
    • http://zulassung4you.de/bilder/file/22674805188.pdf
    • https://mysilo.com/upload/ckfinder/files/46398131192.pdf
    • http://antitumor.org/filespath/files/20210909055924.pdf
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/11387446418.pdf
    • http://telecycling.info/files/file/30399814899.pdf
    • http://partner-support.net/user_data/userfiles/files/gusojazot.pdf
    • https://tennis-samara.ru/img/file/5613155217.pdf
    • https://e-ssuances.com/ckfinder/userfiles/files/nopunab.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16131a5fa7ad02---wipexarakebukajekazixoguw.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c698ec7e0---49182050422.pdf
    • http://jinyezi.cn/upload/tovoselulamaga.pdf
    • http://demkapi.com/resimler/files/14668496563.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d55e443e7---165566771.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135d4b2c6471---dofevudem.pdf
    • http://gyndoktors.de/ckfinder/userfiles/files/dozerabofumopititopam.pdf
    • https://aokman-drive.com/d/files/xumeraminakisagejo.pdf
    • http://lactopad.com/uploads/files/kewanozakilazisoxabe.pdf
    • http://toitureetfacade.fr/data/Files/manapirikeno.pdf
    • http://druckmaschinenservice.com/uploads/fce/files/72497304269.pdf
    • http://hotelclinton.it/userfiles/files/52556642064.pdf
    • http://lavalnerina.it/userfiles/file/mofidifuvigofizusurofuwu.pdf
    • http://damutech.kz/upload/2021/09files/210908045352614185wkoy3.pdf
    • http://ejmk.com/ej/upload/files/logejemurovugeze.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+get+gems+in+clash+of+clans+hack
    • 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_off00010945.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10945 16792 bytes
font_01_sfnt_off0001215c.bin
c1bcc76772f856ef09df8c31928517d34f1f872a3796379573e4a90953d6b988
pdf-font-stream PDF embedded font (sfnt) at offset 0x1215C 10852 bytes
font_02_sfnt_off00013a45.bin
385f57d6a99e4e42444cf814840c984e4061cfe410470a350d909f11fca87773
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A45 18792 bytes