Malicious PDF — malware analysis report

Static analysis result for SHA-256 f37162aefaf6d7e0…

MALICIOUS

PDF

93.6 KB Created: 2021-07-04 09:01:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: df976785b6503f308cf6aeab6f82f160 SHA-1: a712fc564cecbc0bd7d43541622ecd9e0e05c944 SHA-256: f37162aefaf6d7e079c73a95733837ebf7cd50786fd73771640eaf2b984af91f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to PDF files hosted on compromised websites. These links are likely used for SEO manipulation or to distribute further malware. No scripts were extracted, and the document body was unreadable, limiting the analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/9e17e56bf82e0fe3aa58b1717759f54c/54184886891.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/08e7c805b78c052ee973351cbee49c2f/xipogapufavufinimori.pdf
    • https://lotte-ppta.com/beta/assets/file/vasipuvojevowomuvijav.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a80f735cfc4---zusagerisaz.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160881aeb8d5e1---zawadure.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6bf6709fa---19447901490.pdf
    • http://nt-module.ru/ckfinder/userfiles/files/retesed.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/bf27141fad5a6ec7ceaee59092ea6b3a/34385378033.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160db94d57459e---wegitinub.pdf
    • http://hakkabrothers.com/userfiles/file///xajuwirazimijixakuk.pdf
    • http://stellamaris.cz/userfiles/47497132110.pdf
    • http://farashimirooz.com/files/bubuxujefigizorulevilotu.pdf
    • http://skogsformedling.se/bilder_umeny/File/wizixoxesepagolosu.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608f0644ab6fc---xubuwedidirog.pdf
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/5c93fe1405d739ff675fdb382867a144/64045010882.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/63b2cc6c0814f272276f9e6f85f2a8f6/nexexojamu.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608448a6d0e3a---rosoledewibizusi.pdf
    • http://alliance-ic.ru/uploads/file/gifejo.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/beda23130e577f74a28f4aeb3d27c2e4/pejasinipuwolomow.pdf
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/da8c512d4b45d2e5722846eda322a712/55496541585.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/6p8ft17aegv97pjlo2lbis7ek3/tabijinapapujixumovawu.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/f4eanks4hqf5mg8lquhfn15dru/parowajifupugin.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=if+you+love+me+you+gotta+show+me
    • 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_off00010b1d.bin
df2bb15db6118eb81f1a27d22548021303de06c697e592d9250301091a1299cc
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B1D 17544 bytes
font_01_sfnt_off000138fd.bin
b7b77df5d57969f231ade6e7ed8faecb2b937fe3c803da52098e12b422d5b2a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x138FD 10680 bytes
font_02_sfnt_off000151a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x151A7 16792 bytes