Malicious PDF — malware analysis report

Static analysis result for SHA-256 ace0553581a0046b…

MALICIOUS

PDF

89.2 KB Created: 2021-06-30 20:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a860f9d8e1ad71957e2e2e293e319fa SHA-1: 558ac6235c9e86597c5b0a1702797708f82c5605 SHA-256: ace0553581a0046b49b00c75065a400e31a20f61efeb12df829e7c8ec3ccb2d6
96 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised WordPress sites, likely intended to manipulate search engine results or redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the presence of numerous links to potentially compromised CMS upload directories supports this assessment. No scripts were extracted, but the structure suggests a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/1326928093c7cd114af161e803df9af2/69203438694.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093c5c263168---69277363157.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c908bd9445---lemovo.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/cpuu2adturenvespjhfpde7977/14233816170.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/9rioift5hkbtaioea21638b8h8/zujisezubopokuwupof.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2e42ad337---mafomutupekezi.pdf
    • http://madmojo.com/fckupload/file/mofen.pdf
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/f42456067c887cff372cddc976e963ef/fazipodabet.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/8960811b9fde1b0d1afa76463be395f9/wadosoro.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160af19cf19a20---devebakususamonibovara.pdf
    • https://willmarareachamber.com/ckfinder/userfiles/files/gonuvenodudumutuk.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/df5855e58484b07013d2378fe3332075/13626943562.pdf
    • http://lica-mpt.it/userfiles/files/4056473385.pdf
    • http://proreferee.ru/uploads/ckfinder/files/bulaxat.pdf
    • http://hurtmar.pl/Upload/file/kiluromiteweluremoz.pdf
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/97055650355.pdf
    • https://aquafilling.com/userfiles/file/bazimife.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d08b351d1b---95728140442.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/ca848ce8825d869af33f97afb0c21b2a/jezorojiwu.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/ff5a62a147b7f9ac35961aea40ccb4bd/wowugetegibinopoja.pdf
    • http://mp-hd.de/data/aktualnosci_imgs/file/21843938164.pdf
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/tejidojasidogiwafujoga.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160825fc2126e6---vafepixemezo.pdf
    • http://cambresisemploi.fr/ckfinder/userfiles/files/66335140746.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=binomial+expansion+a+level
    • 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_off0000f745.bin
d809025c98eba53ffcaa1c6006ba4430a380eecfe6531bc0c2d7a7c76e0d3bd4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF745 18468 bytes
font_01_sfnt_off000127b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127B8 16792 bytes
font_02_sfnt_off00013fcf.bin
f26f7bc8cc4f33941bf6ece278addce6e0522f331c6f076492318dcd17886c09
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FCF 10436 bytes