Malicious PDF — malware analysis report

Static analysis result for SHA-256 80543899b2497b86…

MALICIOUS

PDF

82.1 KB Created: 2021-07-08 20:43:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c7527aa7fb35bee897c34d33dcae2d53 SHA-1: fdef5b1fb86e6dfb21e65f56e6e67077d1f05e80 SHA-256: 80543899b2497b867b7709fff1deed796cf40b74e7f9ddde520d837b012152fd
96 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by an ML classifier and contains numerous embedded URLs. Several heuristics indicate that the PDF is a link farm, with many links pointing to compromised CMS upload storage and disposable hosting. The primary purpose appears to be redirecting users to external sites, potentially for phishing or malware distribution, leveraging techniques like Spearphishing Attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://nomylo.ru/uplcv?utm_term=nursery+rhyme+quiz+questions+and+answers
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/270b5d55729815a41e102f25518ab68b/tizaxozone.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160e3c95707223---vefoxunijugadi.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/423054d27106f1e60709a607fa2a8c18/45005114036.pdf
    • http://agataklimowska.pl/userfiles/file/putagumasuzeboxen.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16075a6fb3e466---limikaporog.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2428aa0b0---36963198738.pdf
    • https://locoffice.ru/userfiles/file/54188882865.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a099ac3d015---36371623036.pdf
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/d7fsgqfrcvtjic2spogjqofe92/titepivoxexixexatufik.pdf
    • https://corghialberti.it/file/wafosafonojusuworovi.pdf
    • https://jobtiara.com/files/files/pejapegekifipadigetodov.pdf
    • https://najlepsze-w-polsce.pl/uploads/75320739686.pdf
    • http://mega.kz/media/upload/files/mulufimako.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/1e3bfa6a0fac24f08eefca6f77c6b424/54501527997.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/vj6nk6e748163pv7839s6s04a0/luvidufabukefunu.pdf
    • https://binarbaidtrading.com/public_html/userfiles/file/xeviwulat.pdf
    • http://aven.su/userfiles/file/radoseramudirajedo.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c00e81adea3---84074174188.pdf
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/a3c89d0448718c1ac800447b9aab197a/59780634829.pdf
    • https://marathonroller.com/userfiles/files/70093841940.pdf
    • http://18554080.com/userfiles/file/koriwivetel.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9458aa40e5---11627758283.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16075b756984d0---sosef.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/j75obdmea5v2eqd863pp9ut5g4/57010825461.pdf
    • https://tasleemdubai.com/userfiles/files/tikudux.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_off0000dd35.bin
23a5d5bfde01cc7d0b0235040db2436485861bf5ad2874ceb75f70eeeebb9580
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD35 10948 bytes
font_01_sfnt_off0000f65f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF65F 16792 bytes
font_02_sfnt_off00010e71.bin
a725a0bcb98a9911d70de9ecf445e284bb7a731ba0182797575da3ed5a675f2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E71 17028 bytes