Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f41e19bc7154fa…

MALICIOUS

PDF

75.0 KB Created: 2021-07-05 12:03:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8232e802d853db0ae58588a384b907d0 SHA-1: d9f386b987fd3b2345de154a3e4f4107f42a346a SHA-256: 28f41e19bc7154fae74f7e1de5304d5e1e51d165932a9c08b274d5d5b954d17b
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress installations and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/fe8247d78f95bf09be27f04691a6b4ca/40820464201.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607883742bb29---ganagupezigetiwanor.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160781d049dc06---sugixoruneno.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/6n33i2oifj0adts2nlb313dd3i/86114390096.pdf
    • https://naoshima-habitant.com/92629139624.pdf
    • http://brooklynsmokeshops.com/admin/images/file/24518850878.pdf
    • http://vizesblokk.hu/files/file/gikifikuzatapodudotezuwi.pdf
    • http://asbazainville.org/userfiles/file/38326174028.pdf
    • http://santamariamikado.com/uploads/files/kemiwozibevizipenulevep.pdf
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d8975a3b8---5034579981.pdf
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/a94335846ec2ff3350fae19716834a09/9283652525.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c320c120e0b---parenegifava.pdf
    • http://x04ydivan.ru/userfiles/file/23835929705.pdf
    • http://ufnk.fr/app/webroot/files/file/98007252252.pdf
    • https://paklya.su/design/img/upload/file/14789010358.pdf
    • http://jkohut.pl/file/50127211323.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac16a9b63c---79892853447.pdf
    • https://baobihungphu.com/media/ftp/file/xifutegofiseximajavujone.pdf
    • https://pakistanchristiancongress.org/userfiles/file/58111828923.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/d7524009b6bf9095d07e99c61cb9a91f/41560902965.pdf
    • https://vntdc.com/upload/fck/file/werupurexonajip.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/e1c522d8be27c187fb5f6a6e12434b1f/winakafababojitax.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=coplanarity+of+four+points
    • 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_off0000c1f2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1F2 16792 bytes
font_01_sfnt_off0000da04.bin
0a482597a784fab01c3ca5c1336fe818b26d38f102b0fd8df66feacb12811d51
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA04 17148 bytes
font_02_sfnt_off00010713.bin
6ea3b3d36e0d6f2ca75d4b29232353461265c2e4d23fc2e2f1834f53203d1ecc
pdf-font-stream PDF embedded font (sfnt) at offset 0x10713 10464 bytes