Malicious PDF — malware analysis report

Static analysis result for SHA-256 944fd3a2c00da132…

MALICIOUS

PDF

84.8 KB Created: 2021-07-15 12:43:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e24d1a117f10557f19542dd7940ed728 SHA-1: c3a8b6934aba5c99f7e3a160ee937011979860da SHA-256: 944fd3a2c00da132a72d271c172fae56dad80cc77a65076b566233751a123ce3
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple distinct hosts, many of which appear to be compromised WordPress sites used for hosting malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure and numerous external links align with the 'link farm' heuristic, suggesting a tactic to obscure the ultimate destination or spread malicious content across multiple compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9834

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 http://psfund.org/public/uploads/files/cms_files/5714035198.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/439b73d6e5e870044f5fb3127615e6e5/99825536712.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/638bc9212328dd366b468670ee059707/xukuxinonerekubutikusosow.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b402ab5c1b5---80968824756.pdf
    • http://maychamsocda.vn/images/userfiles/file/vezaxo.pdf
    • http://learnazia.com/fck/imagesfile/jarulopoxijikurakura.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac567f32261---juvabe.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b218beb8ec---ligatelovamakadolurosulof.pdf
    • http://hopkinshigh1988.com/clients/75739/File/wumujufidejebewawo.pdf
    • http://leaguengn.com/userfiles/file///nepajulifawuwe.pdf
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/b273d3f4668ddd0e59524ac532de95af/bakogizepaxomusijum.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160805a456435a---webamolalitezipoworotog.pdf
    • http://yilip.net/userData/board/file/35501289242.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c54b3485a4---59840955792.pdf
    • http://coytex.net//ckfinder/userfiles/files/sudigi.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160920feb7df5f---bijukafuw.pdf
    • http://playeasypiano.com/resources/fck_images/12471814948.pdf
    • http://contextuae.com/resimler/files/xonakiwatipigopoforoje.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080d7654d881---sofijajagabaduk.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d3788ade6f2---dedoxonudadopexeruvu.pdf
    • https://llsindia.in/FCKeditor/file/2476953729.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16079fff2033fb---35627195462.pdf
    • https://samowar.ch/upload/file/91194308665.pdf
    • http://sergey-yushkov.com/pict/file/dififofidatibadi.pdf
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095f50ae759a---mibapobu.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dccfeb40b66---xokezuxosububuwojuwa.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b68f17e2ad---jature.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=i+94+replacement+fee
    • 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_off0000e985.bin
41b8bc7662d3c3c9d8e5f46634c4de72d6c3313fb185e87d0836ae3c11d6cd36
pdf-font-stream PDF embedded font (sfnt) at offset 0xE985 16480 bytes
font_01_sfnt_off00011474.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11474 16792 bytes
font_02_sfnt_off00012c8b.bin
312a41349395a0c83a6bcfaa75ecbfbb80e4883a8fe924c750bc36753f8bab0d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8B 10456 bytes