Malicious PDF — malware analysis report

Static analysis result for SHA-256 4893bf11b831db50…

MALICIOUS

PDF

85.5 KB Created: 2021-08-04 11:47:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4efa318d1d73ebcf61998b86e6b3a1be SHA-1: c27e8a46c2f3242f34dd76bca3c3523df391ec0d SHA-256: 4893bf11b831db503dbd17775c8a6abae6ef2cdaaa094d686d02cdf5e17ee45b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that form a link farm, likely intended to redirect users to malicious sites. The presence of these links and the overall detection by security tools suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://coretry.ru/uplcv?utm_term=combustion+engineering+second+edition+pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/3s583m0uosht2r15q08i4ge6r2/diralabowewimodil.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdd00869ec8---mixitusemukovizevaxukagit.pdf
    • https://ajitcoatings.com/uploads/37509917569.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/f5d3cf58112ea4f4efc71193e3dada22/jameguxobot.pdf
    • https://aviseco.ro/userfiles/file/45460823959.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/179c0fc793e35f1b24905f4530646290/28528867898.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/vho26krs9iah4jmkjrpb22t3u2/namujo.pdf
    • http://naturallabs.de/userfiles/file/98277556566.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7c290e608---rorekidusumodapaga.pdf
    • http://china-zzld.com/uploadfile/file///2021061004212714.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7b76f2bc7---rurufafevetekowufuziwuv.pdf
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607edd66db012---raguzemazim.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16071cae3a918a---11963773100.pdf
    • http://cancercareresearch.com/userfiles/file/vuwujo.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/650a4b0d7482e9e5e3e4e80167f96f18/mevewanodu.pdf
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfacd6c722---poviduvagijomizidedobume.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608abe8924d5e---foluxobivobipimasuva.pdf
    • http://sanarina.de/ckfinder/userfiles/files/23835648494.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/1638b47b8a2bc60ae79a15185a6d7b5f/naxesasedivoz.pdf
    • http://klefmarken.se/upload/file/83199876541.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076d29a3c035---tojorudinokukamafuxor.pdf
    • http://ropesadventure.com/d/files/penovipove.pdf
    • http://studiosimonepantaleo.it/userfiles/files/95979291193.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c07c5d4e8a0---3473960676.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_off0000e559.bin
9c17009a803423e48c39b4a45364a201c41a44304770bd5f8e6fd91cdb300325
pdf-font-stream PDF embedded font (sfnt) at offset 0xE559 18960 bytes
font_01_sfnt_off0001156c.bin
5eb62e23fdac9c9328159a3fef28858c377f043fc9a33de1aed3218d5769c419
pdf-font-stream PDF embedded font (sfnt) at offset 0x1156C 11028 bytes
font_02_sfnt_off00012eaa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EAA 16792 bytes