Malicious PDF — malware analysis report

Static analysis result for SHA-256 61e0a06b8f769522…

MALICIOUS

PDF

88.0 KB Created: 2021-07-04 13:25:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a66544e92435fa505c64fe8dc85117f7 SHA-1: 4463741e52af03547539b373645e67a9f9757419 SHA-256: 61e0a06b8f7695223a0f6fc331d37230f7d0fe6017854c9582969b3d17872237
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the exploitation of PDF vulnerabilities or social engineering to redirect users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • 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 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://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/69cead8fa6fbafcee0de0237c582072e/megiroto.pdf
    • https://hondamienbac.vn/userfiles/file/76649517664.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5396b578b---mefokodawijepiput.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea5a8821a0---57030250470.pdf
    • http://riggi.ru/userfiles/file/poxefaxolozadimib.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/d97fa3433d2dee58d1899becd0722d46/20519875193.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/4f2fab347b1d5c43489a0fe16149f08c/nigutonutixilil.pdf
    • https://hometeamcorp.com/images/usr/xonenesimikelikoza.pdf
    • https://ascinfratech.com/clientprojects/trading/file/balilad.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a55518c51a---tateduvizumimuluk.pdf
    • http://cityfate.com/files/files/97866455730.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2957b194ef---53963463542.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081fca199139---sufudenabifusepuvanor.pdf
    • http://nitexprofi.cz/userfiles/file/53178064662.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/4336c0dde7a66b00a59e880f1b33f16c/14764551060.pdf
    • https://iwnta.com/userfiles/file/kizadatuxuz.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607462480e5ac---5020811552.pdf
    • https://aspirans.com/files/file/votidusurefegegubedaja.pdf
    • http://etcad.net/np/upfile/file/8341516368.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/ua133s3e9krpr71kpufciiqvh1/18806391507.pdf
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/dd9ed115917f8ec938d77d0fc442df20/48481227190.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=pdf+to+word+converter+for+linux
    • 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_off0000f395.bin
544e16925e5d61c2c800800ae0ad8c41eebb5d1d0f904e8dd2a0b3e95a0f6dad
pdf-font-stream PDF embedded font (sfnt) at offset 0xF395 10492 bytes
font_01_sfnt_off00010b9d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B9D 16792 bytes
font_02_sfnt_off000123af.bin
ab5a416540e75a6284603defa9c21a22a75dbffb9cf2e695d70b99ce1f15a725
pdf-font-stream PDF embedded font (sfnt) at offset 0x123AF 17952 bytes