Malicious PDF — malware analysis report

Static analysis result for SHA-256 4373f06486ca1a2f…

MALICIOUS

PDF

82.4 KB Created: 2021-07-25 22:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 32fb4d80b1900a8743b5bd06703ed3bf SHA-1: 12b008d85ff904edffbee4dfc72ed4bed038da9e SHA-256: 4373f06486ca1a2fbe27428b8893793eef3176aae72828127c20ced23f7bdf5a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains a link farm pointing to compromised WordPress upload storage, suggesting it's part of a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee7add19efd---jerudijot.pdf
    • http://planetamama.ru/files/file/73387970023.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/7fc21da0e3dbf26502805003808429f5/7502907415.pdf
    • https://mn-lawfirm.com/box/userfiles/file/75178244782.pdf
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/4bb96f229fd7ccaf6fbeb2e90c8e5512/18624277536.pdf
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/bedova.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608130068fde0---93862536050.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a11f0132140---49864627553.pdf
    • https://pinkrali.com/calisma2/files/uploads/lolunivudaga.pdf
    • http://foto-klub.dk/userfiles/file/divujojanowupusi.pdf
    • http://sushiosushi.com/uploads/files/76351480514.pdf
    • http://wallawallahighschool1968.org/clients/75819/File/99316253260.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/16087464869988---8370781227.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b7e9da56d---valugumosuzogowalogo.pdf
    • https://weeb.nu/userfiles/file/57626695959.pdf
    • https://bahamianbrewery.com/ckfinder/userfiles/files/40044081693.pdf
    • http://aimic.com/userfiles/file/famajuzumine.pdf
    • http://webinaris.eu/ckfinder/userfiles/publics/files/901987019.pdf
    • http://joyear.com/ckfinder/userfiles/files/vexirukesuxalikegege.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160724362f130d---70338818138.pdf
    • http://slanfusa.org/clients/47225/File/85085821416.pdf
    • http://geometrarontani.it/userfiles/files/gukelunevebuxa.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed630117cd4---xiwibovoxixotefetava.pdf
    • http://sicilyontable.it/userfiles/files/wupisonokowake.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=samacheer+kalvi+10th+maths+guide+tamil+medium+free+download
    • 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_off0000dbcd.bin
abaf4b9a952f530c38c956d79beefb01c9856a0207dbcdd0089261013ebde84e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBCD 16592 bytes
font_01_sfnt_off0001071c.bin
db47193e2fd0ce5ea5761eaa09b8128ccadc871aae8d062780da9d7704c74648
pdf-font-stream PDF embedded font (sfnt) at offset 0x1071C 11516 bytes
font_02_sfnt_off00012213.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12213 16792 bytes