Malicious PDF — malware analysis report

Static analysis result for SHA-256 838b61783fc85093…

MALICIOUS

PDF

90.9 KB Created: 2021-07-16 18:47:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f505513f1619fcbfb5a322d7da1e74ba SHA-1: 9dc606125c15ddf35abb4965fc6832a3b3b640b0 SHA-256: 838b61783fc8509390528da89534b4694de7c54ce895c2c26cef284ce3445c7e
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is unreadable, but the heuristics indicate a pattern of hosting multiple distinct links on various domains, likely to obscure malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/897bf14ded1909de67282d9efe26091f/10509575183.pdf In PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/fuzudinezejuritafadibub.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/ej8sd5ojato5qimfp26nmcmv12/51026609799.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb6f26571f---31976950500.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/9f2c972e7f4de943e1652957bd3ba062/luwajajanase.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/51699556009.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/75243641343.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607961dfc3166---10726886957.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608e52abea1d4---lojosebag.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb3a7092d8e---sekateruwezuzado.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/210193d320273d938771ed04f90bb4e6/bosekunomozitoz.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608206ce52ee5---fukogizuvusaresi.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16087c50ee4abf---90491765647.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/bb023f013d7c211dd41dc9d9d112a63c/dupogukepisuveju.pdfIn PDF document text
    • http://travelport.pl/userfiles//file/29197465677.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/rijekatenodukip.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e378743803e---gowetixemopirujeremewuzak.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/7397b1faf91eeb22a2af67c1a094d0db/suveligadugisazebivu.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609207bc6e424---bofixefadukoto.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/24db2f7a10f63455dc73253da56225b5/giwemupufowevidevex.pdfIn PDF document text
    • https://pioneerlift.com/upfiles/editor/files/81946843138.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/n4mb1bdnclsuhpknepec76vtmd/gawafare.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609185a9cf939---4677305831.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/87925343071.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+host+minecraft+server+crackedPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fecd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFECD 10928 bytes
SHA-256: 9da3569a52c042fb543ee00d0b22898e89cd492b2f87a116552c958c6791d14d
font_01_sfnt_off000117f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013008.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13008 17572 bytes
SHA-256: 8c87b200f1bd50f08eb4bff5535af5bb04d63fc7bf8c21edde572b14cc89206a