Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a390599ed20540…

MALICIOUS

PDF

99.5 KB Created: 2021-07-04 22:36:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40f7814a8b669790661476fd877823f9 SHA-1: 486693a02ff582af1c29f677671d4680be2bfc36 SHA-256: f4a390599ed2054014180410264efef5453ab64e7c6b00b3b6b8d927f6e5f8a3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. Additionally, numerous URLs were extracted, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c54ceeebec9---1759964122.pdf
    • https://triosms.com/userfiles/file/28456345545.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dadc61ea4a---80046891024.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d3b273294a3---xefogipikamep.pdf
    • http://bsa.by/ckfinder/userfiles/files/2554788855.pdf
    • http://ototavandosemesi.com/resimler/file/57701420256.pdf
    • http://paillasse.hu/userfiles/file/14490605023.pdf
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/6c047c6b7f1e70154efa26271e9f6039/berolax.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607529f78fc67---bituxefagevikebusenele.pdf
    • http://tipkeo.com/js/ckfinder/userfiles/files/vusobupuva.pdf
    • http://hifimarkt.eu/kunden/kronhardt/ckfinder/userfiles/files/74078634425.pdf
    • http://edanieltour.com/FileData/ckfinder/files/20210529_B6C68E3758E2577B.pdf
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/632f335d249c4b1c9513a711172b0aa6/60141939677.pdf
    • http://angelojrobles.com/admin_initial_test/userfiles/file/24843674692.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a822182ef96---bofanerez.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/nnm5u1mf2g5vhtjlfaitatslhh/vofofike.pdf
    • https://dm288.rs/slicice/file/derojipexurowezutidafap.pdf
    • http://www.heksan.com.pl/file/zopemoga.pdf
    • https://sitpchemcieszyn.pl/_sitpchem/file/59185545796.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072429927a7e---neximofujekesesa.pdf
    • http://amoy-art.com/Upload/file/36665894037.pdf
    • http://pobierzplik.pl/uploads/files/jewusat.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/30cf6ef136fb5951875b9e76f81b6ea7/giwunuvunitij.pdf
    • http://goref.ru/files/file/48635357973.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1607af986d09e4---42322150662.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=causes+of+nose+bleeding
    • 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_off00012175.bin
7af514da2524c255acefbb4fbc5297eaf59b7f1656154a7e1ecb3a6955d9a8ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x12175 10600 bytes
font_01_sfnt_off00013986.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13986 16792 bytes
font_02_sfnt_off00015198.bin
63118a86a348ecdaa4f0c1560257db138211e0db830b32c625d34c45642dd71c
pdf-font-stream PDF embedded font (sfnt) at offset 0x15198 18044 bytes