Malicious PDF — malware analysis report

Static analysis result for SHA-256 b146f43c3f8d4ebb…

MALICIOUS

PDF

89.8 KB Created: 2021-07-02 01:52:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9e60ac246787cce2262f931568526205 SHA-1: a7ab6e9ad6ac2968f223caa0e0c10ec3301e3d87 SHA-256: b146f43c3f8d4ebb02a87d055113eb9cffba75e1ebd300ee11085aceab4030d9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload directories and other external sites, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the embedded URLs are the primary indicators of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://laborke.ru/uplcv?utm_term=cheers+to+life+quotes
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c029786a975---26482020251.pdf
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2df134a55e---75968149106.pdf
    • http://eortak.com/img/fck_temp/file/41605389302.pdf
    • http://vmkmsz.hu/userfiles/file/64881134932.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/a7ea0c7b9d0e12223bd6417112052973/buxoxefolin.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087da05dbaca---vamapexem.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ad41adedd---23992390653.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a332b74e0---84224640991.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/kjtiucbqsc7glnv48or6mn53e2/97129903888.pdf
    • http://globalaircrafttech.com/ckupload/files/34546519685.pdf
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec22b4d01e---45274976695.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b26a7a24a---filuralawuzijemamulipewe.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/65920917300.pdf
    • http://asfalon.com/__files/file/xuturiwobevaju.pdf
    • http://sierrahighalumni.com/clients/878712/File/jamezuz.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/7a0f9d122c116fb255260ce60611ebd7/ruxebutidi.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5cd9ea58fe---14858038921.pdf
    • http://franzoesischebulldoggen.eu/userfiles/file/37150104602.pdf
    • http://indago-rovigo.it/userfiles/files/vonovib.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083089767c21---69721970133.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609acb2abc8eb---29341042109.pdf
    • http://timandlor.com/userfiles/file/labunaribotubapirifu.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_off0000fc98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC98 16792 bytes
font_01_sfnt_off000114af.bin
fd1dfea56b43387450c6a076c86fdf342ac7f8d9d9b39d8f716b9d40597cb89c
pdf-font-stream PDF embedded font (sfnt) at offset 0x114AF 10324 bytes
font_02_sfnt_off00012c1d.bin
544b9417659835778597519a08bffa29ac94ebbae5cdc792c76d38ddb8371805
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1D 17260 bytes