Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98ec597246fdb6e…

MALICIOUS

PDF

87.8 KB Created: 2021-09-20 08:42:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 96666e39cf8a952426b678c0854a1918 SHA-1: 5dd9210dac9d2b16e142633fce480192e8f8242a SHA-256: a98ec597246fdb6ed5f8896775ed5114d248709574b61a5fbf9a0fc60cd8401c
146 Risk Score

Malware Insights

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

The sample was flagged by ML classifiers and ClamAV as malicious, with multiple heuristics indicating it is a link farm on disposable hosting. The PDF contains numerous external URIs pointing to potentially malicious domains and IP addresses, suggesting it's designed to redirect users to phishing or malware download sites. No scripts were extracted, but the PDF structure itself likely facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://krisoc.ru/uplcv?utm_term=how+to+block+apps+on+android+phone PDF link annotation
    • http://cudicio.it/images/file/12207105337.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/rudusabediki.pdfIn PDF document text
    • http://www.primariasantana.ro/uploads/file/sotedusanabifewojow.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be087b924a---renuzot.pdfPDF link annotation
    • http://technology-mp.it/userfiles/files/77705997391.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/41754533456.pdfIn PDF document text
    • https://promise-land.com/upload/file/gavum.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/lesuvo.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145525e96dab---mozuturukane.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/verajuvusewofewujuxovem.pdfIn PDF document text
    • http://vnationwide.com/userfiles/files/xewomabakiwijawubibibaji.pdfIn PDF document text
    • https://valenciamaids.com/userfiles/files/bogitepali.pdfIn PDF document text
    • https://96662888.com/editor_upload/file/70991984925.pdfIn PDF document text
    • http://gibisch.info/files/files/88038208187.pdfIn PDF document text
    • http://elcwma.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rasus.pdfIn PDF document text
    • http://prestopc.it/upload/file/47279872019.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/66163881527.pdfIn PDF document text
    • https://bacsionline.net/userfiles/file/kabegekoperu.pdfIn PDF document text
    • https://viscom.bg/uploads/wysiwyg/files/lobidudexufanatazoro.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/pasupal.pdfIn PDF document text
    • http://lemonsport.hu/upload/file/batatofu.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/9f0728c08152cc1815c3486a5a6178d1/51915016625.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/pazobut.pdfIn PDF document text
    • http://tw-jia.com/uploads/files/202109200052308796.pdfIn PDF document text
    • 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_off0000f123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF123 17844 bytes
SHA-256: 00cddba8be193e10811aa935119c82a287e177e7456680a7ef8bb2c39dffe139
font_01_sfnt_off00011fde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FDE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000137f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137F5 10920 bytes
SHA-256: 0c2f0902cb93d496e4bd0fd6a0330eebdb4042c8602b4c3afefe7cf5d9f470b4