Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a899b42dab76540…

MALICIOUS

PDF

69.1 KB Created: 2021-09-26 14:18:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6b9f0cc973e7593e055d75e1c64194f2 SHA-1: 367a14ac86a5627bc8b3370df4a4b485ca758722 SHA-256: 8a899b42dab765406897bc14b2dede89cfe18a90ccba7b787897c1741a2e60f0
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDF files hosted on various domains, many of which appear to be compromised WordPress sites or disposable hosting. The heuristic PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM indicate a pattern of distributing malicious content through link farms. The ML_NYX_PDF_MALICIOUS and ClamAV detections confirm the malicious nature of the file, likely a phishing or trojan distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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=sniper+3d+diamond+hack+mod+apk
    • http://walosports.cl/userfiles/file/pegupopenugaxi.pdf
    • http://wonsakai.com/uploads/files/22100922102.pdf
    • http://exms.fr/sites/default/files/file/83060493687.pdf
    • https://tsegypt.com/file/sejutaronukid.pdf
    • https://www.jancsoalapitvany.hu/ckfinder/userfiles/files/fumataton.pdf
    • http://boilerservis.ru/uploads/files/83221195356.pdf
    • http://pk.mo/userfiles/file/91206639231.pdf
    • https://www.sterlingsez.com/ckfinder/userfiles/files/mivinoz.pdf
    • http://liccuza.ro/stiri_files/file/70604359142.pdf
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/48838208325.pdf
    • http://cherryontop.pl/upload/fotki/file/14557405736.pdf
    • http://shortguycentral.com/ck_uploads/files/48400939055.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614729353cd6a---57344396364.pdf
    • http://vom-ragnaroek.de/uploads/file/86893495396.pdf
    • http://nceed.kr/pds/userfiles/files/12499852365.pdf
    • http://bulgankhangai.mn/userfiles/files/puxelu.pdf
    • https://futurefacesmiami.com/uploads/file/11452438206.pdf
    • http://carraracucinecomponibilitrapani.it/userfiles/files/55942980048.pdf
    • https://tp-pos.com/uploads/image/files/34030990632.pdf
    • http://naturalwonders.com/uploads/files/vidofedivarolezujug.pdf
    • http://timandlor.com/userfiles/file/14035221790.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16142b5abe522d---kemojipuxe.pdf
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/8935171064.pdf
    • http://specimport.by/files/files/47993577671.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1613625b9cb08e---11138989006.pdf
    • http://zhouzhuanx.com/v15/Upload/file/2021926160234046.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_off0000b002.bin
d0ca25bd1c8a7e56d05086d3b1a33dde8ec072206a9e530223837eff4b483f89
pdf-font-stream PDF embedded font (sfnt) at offset 0xB002 10808 bytes
font_01_sfnt_off0000c8b1.bin
1919d21028d0b2675ed5cc05bac65143e038ccd0fae4348691d4e2eb7fdb7ae7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B1 14884 bytes
font_02_sfnt_off0000ed40.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED40 16792 bytes