Malicious PDF — malware analysis report

Static analysis result for SHA-256 921827d875d70cc3…

MALICIOUS

PDF

87.2 KB Created: 2021-07-28 11:33:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4f5a964d218baeb5b015a799de76ad98 SHA-1: fa36f939928dc8d8cef39404dfe32ae9c21d90e4 SHA-256: 921827d875d70cc32125db84519b7ce430d769cb79e939832592fa8625aea492
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or SEO manipulation. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/5b5fde78d35a9f16ec0dde0e4c3706e5/55097084199.pdf
    • http://metabolit-plus.ru/files/file/37169500063.pdf
    • http://tfwdynasty.com/clients/f/fc/fc55782506b94f933057639757072b2a/File/76734596871.pdf
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/n86i355v8jep2eah9e804ao2ek/punibazij.pdf
    • http://alpha-th.com/userfiles/file/gafafafunomeragotup.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/10c5213e1cf38d78b6e687ad1b64bbf7/gojuxojumab.pdf
    • http://moscow-vernisage.com/files/files/lebofibukasodibitajexor.pdf
    • http://dgjst.com/upfile/file/xikakid.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc024e07b2---19139086601.pdf
    • http://www.gpe-el.pro/ckfinder/userfiles/files/futokumabokubope.pdf
    • http://pamat.ro/UserFiles/file/75398470597.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/sng3ufaesgfkdi7u8lavhh7nmg/nedekazumevudunoz.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/fcaec23c410f474c4ea0fabb657e49ad/90504669655.pdf
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/bsou1teickl9h4q550anjj5657/98304720314.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608893e363d19---mumaralerawunotepukalano.pdf
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/26588930534.pdf
    • https://clubkdo.fr/img/pics/files/vosokexomirovuwidi.pdf
    • https://ht-cooling-j3t.com/contents//files/9582618282.pdf
    • https://partnermind.cz/images/files/39527823951.pdf
    • http://businessvaluationapp.com//fck_files/file/kemowaja.pdf
    • http://snailgame.ru/upload/files/20210726095957.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/is9kfg7pbbjnv46ga81nug65ac/66246927650.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=how+to+file+a+subpoena+in+california
    • 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_off0000ef21.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF21 16792 bytes
font_01_sfnt_off00010733.bin
81c779663d96b29098da286c239d7d6e347faa58e4fbbeb8419f8bcdb85b567d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10733 17924 bytes
font_02_sfnt_off00013624.bin
1f6b3c69acfaa6218bf9d2841bcb2a74895648769d1ad720bc0efae86b65823a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13624 10792 bytes