Malicious PDF — malware analysis report

Static analysis result for SHA-256 863b88d1b2946000…

MALICIOUS

PDF

73.2 KB Created: 2021-08-31 11:14:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67b0500be55414e635a1096c16ac72a5 SHA-1: 2f1521ff7c3869064474d1a44d7288fbd8e30696 SHA-256: 863b88d1b294600008c607f4b33644adb999ee5765689e0173ca20617b1f9f06
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, indicative of a link farm designed to distribute malicious content. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The heuristics suggest the document is a link farm on disposable hosting, likely intended to lure users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=digestive+system+coloring+page+answers
    • https://propiedades.net/ckfinder/userfiles/files/kozivamego.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612a55fb3d28e---kalaxejasemik.pdf
    • https://maintogelonline2.com/contents//files/tuxixasixedekepe.pdf
    • http://wittlich-luexem.de/userfiles/file/tuvujidefitotom.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/pizodiwigim.pdf
    • http://tele-video.ru/upload/files/27806378861.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087850ee48e1---10424839209.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe1bec68ff---64706307322.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610c2ac951fa3---37445160834.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0d38bbe25---34167986126.pdf
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/06eaea84928241552ae7f78375644dd5/612778324.pdf
    • https://koratspring.com/upload/file/5455880682.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/s07n5rthd6889apl9jv4h29j75/rakupenukugudemafolosaro.pdf
    • http://jsushibrea.com/uploads/files/teluzurogilonuma.pdf
    • http://dabaizhongxue.com/upload_fck/file/2021-5-15/20210515032850564242.pdf
    • https://saikekanglun.com/filespath/files/20210822053405.pdf
    • http://artin-intranet.com/ckupload/files/26241076269.pdf
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/5686an747031g4fc8i1qdivhea/71569682408.pdf
    • http://ottotech.center/userfiles/file/41356628965.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a89cd2be341---ditimor.pdf
    • https://tutorsbureau.net/userfiles/file/47577310752.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_off0000bda1.bin
1f2621600ebb23e20b81e464def596cbb36c9d391aa03d38838fcecada97b2c2
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDA1 15560 bytes
font_01_sfnt_off0000e4f2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F2 16792 bytes
font_02_sfnt_off0000fd09.bin
8624a2c4e22d96f0caeb9926aad4c09763f8ccb5d3f981cea45eb6b0882e2a6b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD09 10984 bytes