Malicious PDF — malware analysis report

Static analysis result for SHA-256 54818251a7b28edc…

MALICIOUS

PDF

86.3 KB Created: 2021-08-20 17:12:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a5c0f388d6396d95d2b9c116874431f2 SHA-1: 5ae4951ba8a5d0d716ad6675d410fa4d5ad9d787 SHA-256: 54818251a7b28edc5b8ae290b89b59c7244defdbd2a9aa99cdb4a06f0d9729a1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://catamma.ru/uplcv?utm_term=maya+angelou+graduation+rhetorical+analysis
    • http://sh-songshi.com/admin/upimg/file///tavefopagola.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abbb5241b4a---89033679294.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611e7306c9278---99289534505.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/4e470063ca53818ce6fefc24eb8175a7/14175454826.pdf
    • http://hnsunnyfood.com/d/files/7495093177.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f851caa8b8d---wejarowevelowakafiz.pdf
    • https://doina.md/fckeditorfiles/file/kebaxafala.pdf
    • http://gshosnab.ru/userfiles/file/5318327059.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609850ce892ed---45589120634.pdf
    • https://istanajp2.com/contents//files/sakizelok.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/06674c252a6657bebbd9c7000afa7e4a/7972924694.pdf
    • http://hongshengfish.com/uploadfiles/20210606/210606123005894103srx7mz9t11jd.pdf
    • https://gifarlcm.com/upfiles/editor/files/vuridageretibuje.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/kuvqf0ohmbkvfco7tfa3sr2j92/1148082913.pdf
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a4315a1f7---68895845469.pdf
    • https://justbuymeds.net/userfiles/file/7318213061.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c97586a0715---29368762107.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160792426a749e---40662435206.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/16ed4fa487ac9d9af70e0dc300ab41db/vejugavobi.pdf
    • http://staresecurity.com/userfiles/file/37004505769.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160acb06e6c152---77591109450.pdf
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/a831040e7e9d75c45e62a626cc25101a/fomasasosimedevanejizixa.pdf
    • http://abpaluso.com/upload/file/xopexonidutogajetokugu.pdf
    • http://nguyenquangcomputer.com/upload/ck/files/biwop.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_off0000ea7e.bin
7910ed5068e6d648e7d4a76408c26a00eb171191debce76c9275efc9cacd4f95
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA7E 10856 bytes
font_01_sfnt_off00010356.bin
e27a234d80734a7b0ce941081935d9f9536d233761e98db8522fa6eb8037ff02
pdf-font-stream PDF embedded font (sfnt) at offset 0x10356 17884 bytes
font_02_sfnt_off00013068.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13068 16792 bytes