Malicious PDF — malware analysis report

Static analysis result for SHA-256 b623ba0de2373fe8…

MALICIOUS

PDF

96.3 KB Created: 2021-09-01 13:57:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea5952e7c6d298897cb283baebe0930b SHA-1: e7b37ab3d0da4a9175d854e906702940640870f1 SHA-256: b623ba0de2373fe8d6e76dca114c115c56af100a88d8f8b7be46c9e4abe89560
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://samarthanamparisara.org/apadmin/uploads/userfiles/files/45735455238.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083167b8dd7c---vefazuwugegogudemanofitiw.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3a5db188d---25845476307.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e0d809fe1---21136536459.pdf
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/zivenebikisig.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/cb52e16344b6511a76a8d83f8ea30865/40864904627.pdf
    • https://conexus-study-abroad-travel.com/ckfinder/userfiles/file/pidilexu.pdf
    • https://footballsod.com/images/ck-uploads/files/2671297133.pdf
    • https://ukmalayalamnews.com/userfiles/file/nirenadakopizoregivofegix.pdf
    • http://ptairsupply.com/userfiles/file/bibizibawikito.pdf
    • http://simonhoirup.dk/userfiles/file/84978788517.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/rkplgt77jan8565cg3qegl3m15/31291685348.pdf
    • http://sweepinstyle.com/userfiles/file/58903908096.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608df95f4a58a---fokafekeg.pdf
    • https://free-spirit-city.eu/uploads/wysiwyg/files/84857963985.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/467nhns9bv3ndl6lk5pnq1jk74/vaputofutubukejake.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/8e8357cbf8a3d4743ca7c776e7fd5229/nupove.pdf
    • http://www.almansori-ye.com/almansorifiles/files/28773235125.pdf
    • https://aimhc.com/userfiles/file/malij.pdf
    • http://akgikorea.com/file_upload/fck_upfile/file/64815555375.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c111287beba---dabefifefesozibesijap.pdf
    • http://profil-metall.de/content/uploads/file/mosejoneg.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16093a76f18963---ruzibotomodalesaki.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4a988bab8---62971986207.pdf
    • http://zoltysnieg.pl/pliki_wyswig/files/fujosixajabamem.pdf
    • http://rowanfamilyreunion.com/clients/28915/File/jifoxoximelosixulob.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=the+term+quantity+demanded
    • 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_off0001152d.bin
0442d8e7caea86ac9bf67764b422461c77fa52aec37cd34ae4fe23ccf1ebbf08
pdf-font-stream PDF embedded font (sfnt) at offset 0x1152D 10500 bytes
font_01_sfnt_off00012ca9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CA9 16792 bytes
font_02_sfnt_off000144bb.bin
230d8ce129b01f20ab516f612b1f6a773e2f1cd4a6c3b81bc41ae8900673706a
pdf-font-stream PDF embedded font (sfnt) at offset 0x144BB 18004 bytes