Malicious PDF — malware analysis report

Static analysis result for SHA-256 79121851ebe86c99…

MALICIOUS

PDF

71.7 KB Created: 2021-09-21 01:48:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d79fcd7f1537f4042b952b62d2aae89c SHA-1: d8bff21324dc695149e297de9c37a346f705e926 SHA-256: 79121851ebe86c990f0571d5c6c027907096679e7a71c102f11e68df2b9253f3
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. The document functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting, designed to redirect users to malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests an attempt to lure users to external, untrusted sites.

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
  • 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 http://jornalespacoaberto.com/app/webroot/datafiles/editor/files/radutufazoxegefanixafuj.pdf In PDF document text
    • https://asmitahrgroup.com/ckfinder/userfiles/files/fukifedoxujexadakuni.pdfIn PDF document text
    • http://imprezka.2kc.pl/Upload/file/posovufuroloromefotokil.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145aae4ca1a1---1948829596.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/xajuwomeviriwurudifunejik.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614908312c521---49741845791.pdfIn PDF document text
    • http://haiannweb.com/uploads/files/52770408690.pdfIn PDF document text
    • https://samsungdvm.net/upload/ckfinder/files/tavuredokoduwapusipanigoz.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/sekemopobotibofeva.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/zubazivulabun.pdfIn PDF document text
    • https://castilloexterior.org/ckfinder/userfiles/files/85913394869.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///55696173797.pdfIn PDF document text
    • http://profstil.az/userfiles/file/nasifedegomulavekebisu.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/51171928970.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/kivukadewizaba.pdfIn PDF document text
    • http://hkacca.com/userfiles/38532465639.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/nobogizumimunanokanamed.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/19202671388.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/nopopasapobamufas.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/rovixalew.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/6aec2f454a72ff89f03b2172a68a319c/78525074384.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=words+that+start+with+r+and+end+with+hPDF 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_off0000b547.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB547 10380 bytes
SHA-256: 10bb2469aea51c99353ef6929721343332d0c5cabde55d5ea93de8ad858516e1
font_01_sfnt_off0000ccbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBF 17280 bytes
SHA-256: 7e365035e8dc4da3162c3e5a87462f55098a714a3f7aaca34c5ac3c89cc4bef5
font_02_sfnt_off0000f954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF954 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1