Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea8cc5f0b3dd51a7…

MALICIOUS

PDF

95.2 KB Created: 2021-06-27 00:18:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 778870e86e764bdf5f5416608bf0a1dc SHA-1: ab5b22fbe2d1902c4ccd8ba857ec31c94989e435 SHA-256: ea8cc5f0b3dd51a7c9bc42600ca757f3f5f65f28215df5e3165e84ab80a11b5e
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised WordPress installations hosting other PDF files. This behavior is indicative of a link farm designed to distribute malicious content, likely for phishing or malware delivery. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://coretry.ru/uplcv?utm_term=where+is+an+801+area+code
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a9a07df658---73976440912.pdf
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210627061359.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/10c330a32563ff5ae43e900ebd8903ad/gikuxuj.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/fce45fe687558b0cc65214fc3aeda4e4/47622038997.pdf
    • https://wsbtitan.com/images/file/24532096790.pdf
    • https://mkontakt.pl/dat//file/nopojukuminufusetisiloso.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095edb2ee6fb---tavobifaparof.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/ojnjhkhfgbpaobv5odvj1f35a0/tifunibeni.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b94190c69b0---9130688879.pdf
    • http://thanuyentea.com/ckfinder/userfiles/files/85003821.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/692c2a8dd7bcafdcefebb732b01e7cfc/23316216106.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a9cfe21d2d6---16925084519.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160855a83dfaee---2803890973.pdf
    • https://varbackaforskola.se/ckfinder/userfiles/files/24329051280.pdf
    • http://lbhs1965.com/clients/6/6b/6bdd8f708684a1f547efbf97e1630fe5/File/nuguwedurosesejanexezat.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f355c2caf---37367028666.pdf
    • https://landbondcorten.com/attachment/file/7708dbcfd52b186fd9d5126a269cfd58.pdf
    • http://developmentassociationofnagaland.org/nbloom/fckuploads/file/lezaduwixibefa.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/8b5fd68cc72281e1fc03f374f91589d3/525370601.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/7efbb7d909b9b67c8d04e99e3fd81941/liribuxof.pdf
    • https://aawyx.com/sites/default/imageuser/file/48721542643.pdf
    • https://angkortaxiservice.com/userfiles/file/bolapixele.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076dd075ed58---84991437721.pdf
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c400d31fa---16711772589.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_off0001139b.bin
36ba8e6a45f1383282d7c8561dd90e9ff342da3f7534531a1d1b61aea7e79a03
pdf-font-stream PDF embedded font (sfnt) at offset 0x1139B 16680 bytes
font_01_sfnt_off00013efc.bin
2fcfbafb075c83613a94b155d91aecbaf4e76967b6f7b5b064485544c1b49cde
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EFC 10700 bytes
font_02_sfnt_off0001578c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1578C 16792 bytes