Malicious PDF — malware analysis report

Static analysis result for SHA-256 16700f9268bab649…

MALICIOUS

PDF

103.9 KB Created: 2021-07-17 17:07:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c5e4f9f1021d1ca406549de96eb0dc58 SHA-1: f692e7f97806cf7bee95f72d78ca1ec17d39edbe SHA-256: 16700f9268bab649d457c2a398dc8d32651f5125cbbbc1ceb7137a06f4bacc6a
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure but containing embedded artifacts that likely facilitate the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://asupuro.com/user_data/image//file/fixiwikoxosutax.pdf
    • http://hillandcunnreunion.com/clients/864369/File/bixadazozosevaw.pdf
    • https://nikosdimos.gr/userfiles/file/pujokimeda.pdf
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16084bce5d2910---zekobogusarogodutuk.pdf
    • https://acrgroup.nl/userfiles/file/71180086490.pdf
    • http://yorktownhs1987.com/clients/57482/File/fixus.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/9t3t0p9ljroj0envsmdlepq9s3/25071768648.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/munilu.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/m11jdurkd2q9ch14ahe706cnr5/nonowimutinukopezogukeji.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091f0fe0e0c3---fonusowefanerowubepigim.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1607d692a5769e---xoteneganobipajalip.pdf
    • http://aven.su/userfiles/file/52425831063.pdf
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/tf83ao1hnposiandkkjes6q610/51896011715.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef022aae39---87879825688.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608537fbea4d9---34621643649.pdf
    • http://wshs67rocks.com/clients/9/94/942520bde836a0b401740df6f3d23d35/File/bifonukodavijujazitod.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/7b9a6f23c08cf0aba2a2cf53fed851f0/73705432478.pdf
    • https://fnb-concepts.com/images/uploads/files/64400326012.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/r35dvo7m7gjh7okk455av4sao5/92047842526.pdf
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/2f0a187c3bafbe3acdb5765ebb360123/wofakarizisibarukuvofagel.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=famous+females+from+kentucky
    • 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_off0001352b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1352B 16792 bytes
font_01_sfnt_off00014d42.bin
c5c575354d24af40addc642ecb606a62e96a088225484b29e398ed5824b481e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x14D42 10688 bytes
font_02_sfnt_off000165db.bin
a26ed8837f1e69f559c413c3de76957c4cfa40da1d93c097979620000e37e948
pdf-font-stream PDF embedded font (sfnt) at offset 0x165DB 17252 bytes