Malicious PDF — malware analysis report

Static analysis result for SHA-256 fea648ec671b39f6…

MALICIOUS

PDF

86.3 KB Created: 2021-08-05 14:13:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9fd728c534975c5ae0e0d8c6d7df8192 SHA-1: bf6dea80c1090134750765235ad85189e8fa4ac1 SHA-256: fea648ec671b39f6d63e753a2c695f88c9a68febbb4168963a7d706ee3267acc
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbd395eec5---54226502674.pdf
    • http://mebelhotel.ru/images/news/file/kenimewuvavebazajujoxil.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/0i5qc6s704uqobbv18sl7d3udr/85012492466.pdf
    • http://hacoauto.vn/upload/files/zanek.pdf
    • http://vizesblokk.hu/files/file/23562431141.pdf
    • http://venusland.vn/app/webroot/img/files/80591395769.pdf
    • https://allmassage.net/upload/file/20210519111601.pdf
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/a14fffcd6c24da478a6f7338fdcd0ee6/sowefadejejogil.pdf
    • http://recviem.ru/img/upload/lopaninume.pdf
    • https://laflammerouge.ch/userfiles/files/vixezuposarifalitu.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc4e447fb3---guwiz.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/703cfc39183811efc2e146c269c1c7e5/86737956200.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160f48e6d62be8---kunixujixikix.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f1ae79582---5959922649.pdf
    • http://qiuyutv.com/userfiles/files/20210615024303.pdf
    • http://maytinhtuyenquang.com/home/maytinhtuy/domains/maytinhtuyenquang.com/public_html/images/file/77498768750.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608eefab44388---bamofogivopaxo.pdf
    • https://churchofgodinjamaica.org/app/webroot/files/19493305781.pdf
    • http://agierresrl.it/userfiles/files/67399465437.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/f51432d7d9437c2ee5237766dd45e77e/48478797455.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160977ac7ce345---49522613154.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/nqc9o90mcsbpam78v3it2i2341/lodoka.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/d235a2af04156211f58c462031043955/11236965572.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=theory+of+corporate+social+responsibility+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_off0000ee9f.bin
c6e2516c2044190a76cd113ac09e64a074073525e7e2d2bd38f48da5c2d43ef6
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9F 16620 bytes
font_01_sfnt_off000119d5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119D5 16792 bytes
font_02_sfnt_off000131ec.bin
88260b5e29ef306d2d0691b7a9165a9db4baee0437aa8be10897b3601467d5f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x131EC 10932 bytes