Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6a5f8bec1e69867…

MALICIOUS

PDF

82.4 KB Created: 2021-07-01 23:21:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8409a9076f68bc7f70c473cd29b91100 SHA-1: 12f0377cbd0b8705cd94bbdc1cef4b8f3980f267 SHA-256: f6a5f8bec1e69867d8a03e7c4f44d2b254e430e4060edcd8ed2bd8cf5703f54c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous URLs that point to potentially compromised CMS upload directories, suggesting an attempt to lure users to download malicious payloads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but serving as a vessel for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f3cd80e03---sosirebaramepezepoz.pdf
    • http://artkulinaria.pl/sites/default/files/file/veguvepurikubunaxezop.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/jcijtsfd7d9j14755ggkeesovt/9648614235.pdf
    • http://flemingfamilies.org/clients/8/8a/8af36a28baf44bfc7b8a7004fb4eaede/File/foloxedalivonojekumabe.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b80eaa7075---nesebijotemewekuginotagu.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e80f6a2f8---gemubevetuduzametejarogar.pdf
    • http://piemonteforyou.it/userfiles/file/77399268231.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/c53c110e316447cb7c7086cb082f5646/53713319773.pdf
    • https://www.makathastaliklari.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080c83582a6f---besurowav.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/07956fc58946a7bf6d4e1215b367a5cd/45234314547.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/gh7tb14msbt8a8u8pij5lkkn07/64068190639.pdf
    • http://hopkinshigh1961.com/clients/878968/File/18555923678.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16070ceba8a246---sogig.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/13b0d681da6629f5a0c9893a577d4136/kajonogu.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941686417f9---namesolurupijitulekomox.pdf
    • http://www.bufolari.com/public/immagini/file/xenib.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe64775b27---5043400332.pdf
    • http://alkanboya.com/files/file///wurotegebukawojedudo.pdf
    • http://allasclub.com/campannas/file/14564819909.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/5754970cd483fcad791740148f8f7fae/71599179254.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160dd80c76c351---50261493036.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607199ca6410d---fezelipirimun.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79d58a9858---wubul.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d370b2ecb---4629659789.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=fundamentals+of+physical+geography+majid+hussain+pdf+download
    • 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_off0000dc87.bin
9e0c47c914e06a2c46f93bbc239a8c0102e9fc11953aeaa93b3ec568621c1499
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC87 16900 bytes
font_01_sfnt_off000108f5.bin
93043a35ae21bafb0b4639f23ddc40528b977bd2de227045bfbe11a442391f0a
pdf-font-stream PDF embedded font (sfnt) at offset 0x108F5 11472 bytes
font_02_sfnt_off000123b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123B8 16792 bytes