Malicious PDF — malware analysis report

Static analysis result for SHA-256 6da1e3e169f3a2cc…

MALICIOUS

PDF

89.4 KB Created: 2021-07-19 14:04:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc0e8fba72ca6074fb6368c357c2bf32 SHA-1: 8603759b61e659c2fafaf6ed1bfa77d0e8598d4f SHA-256: 6da1e3e169f3a2cc350c91e4560072a6d26bba039b60db7a09f6c27697e24b4f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to other PDF files hosted on compromised websites, likely to manipulate search engine results or distribute further malware. The presence of multiple links to compromised CMS upload directories suggests a coordinated effort to host and distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/1cc884665f541f4844e55dc3be541544/28687116581.pdf
    • http://clinicaveterinariacene.com/userfiles/files/89724156728.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081477eb637f---68343323513.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e6b697bd77e---37357766181.pdf
    • https://bem-sa.com/img/file/21615291070.pdf
    • http://chpcentre.com/files/file/21101796248.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/u9cl7de3nrehtttf9ogf2ut4e5/47442692274.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d29c69ae31---kividofodanolokemovuz.pdf
    • https://quanghuydulich.vn/img_duhoc/files/97331902424.pdf
    • http://stananddiane.com/clients/6/67/672a2699e369d648dd23e03de9deda78/File/napijunu.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948753445c1---fobobutiratologidifu.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/tiridigomoverugugososol.pdf
    • https://primer-spb.ru/files/files/gixibafesitafujorufolaka.pdf
    • http://blessedfamilycovenant.org/clients/c/cb/cb727bc273eb4203dc66fb73741ae5ae/File/58976733392.pdf
    • http://kppzp.pl/userfiles/file/73767326972.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfaa503b51---43807875093.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072baf35a68e---lojuduwadozojoweniv.pdf
    • http://hotelamadeustorino.com/userfiles/files/96566704177.pdf
    • http://newtrierreunion1962.com/clients/6/64/64567561842b0bbd40b956adda0282a7/File/tufupumovirusekomikimip.pdf
    • http://mazdooradda.com/userfiles/file/18528367775.pdf
    • http://barbusci.it/maisUserFile/file/31739756713.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/2123aa1bceec22fca6ff04563dc9002a/bivan.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=indian+reorganization+act+new+deal
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/4ba3a0bf5e080c36943a5fc876c675eb/rikogud.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_off0000fa80.bin
83559264edef45a7522428869bddab3856fc8cbd4b92d6c62fa846b76a6526fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA80 17068 bytes
font_01_sfnt_off0001271a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1271A 16792 bytes
font_02_sfnt_off00013f31.bin
73de4412914bbc22bd2589450b5833e426da479e0ed686d5571771ba6d07af49
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F31 10476 bytes