Malicious PDF — malware analysis report

Static analysis result for SHA-256 81edae0c09031ab0…

MALICIOUS

PDF

84.3 KB Created: 2021-09-17 00:16:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c1dddaa1a28367a1b085d63c37920311 SHA-1: 91d707199200044e47a4e96e596f5c7f72396255 SHA-256: 81edae0c09031ab094118c137f929fccbb73c3c401b0205891396e5cd76244b0
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS upload storage, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://synerhu.ru/uplcv?utm_term=day+one+android PDF link annotation
    • https://superpackeg.com/userfiles/file/temovarujifuvidebafusuba.pdfIn PDF document text
    • http://iweldbot.com/ckfinder/pho/files/93408163930.pdfIn PDF document text
    • https://ckmusicdesign.nl/userfiles/file/88230401903.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/povilezadojixurujufa.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/7828505384.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/46858425585.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/vadebubur.pdfIn PDF document text
    • https://ubitanduk.com/contents/files/8345395812.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/rexabufuvakos.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132826ba03e8---47943107751.pdfIn PDF document text
    • http://tarnava.eu/user_images/file/61562170873.pdfIn PDF document text
    • http://paglialonga.it/userfiles/files/77748044320.pdfIn PDF document text
    • https://armenia4d.com/contents/files/14857048057.pdfIn PDF document text
    • http://unewstoday.com/task/userimages/file/mozapeta.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8b26635fb---48198554540.pdfIn PDF document text
    • https://loyallcanada.net/editor_files/file/43075693583.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-16/20210916220206669053.pdfIn PDF document text
    • http://designgaleria.hu/userfiles/file/satasizusezo.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/k9kfvf8cg5slae113g06904fp1/5269685035.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/wonanawuvu.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/54645797246.pdfIn PDF document text
    • https://peptidturkiye.com/ckfinder/userfiles/files/jufiwajeluruv.pdfIn PDF document text
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/durujiviwo.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/27063990946.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/38890988307.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_off0000e59d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59D 18200 bytes
SHA-256: 62412228f3a2630d23bae414d4b2b82d76a13acd8ca4e6c83f30bb3cdb578412
font_01_sfnt_off000114f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D0B 10044 bytes
SHA-256: 90d165d15b42770e63d420aedcb9b1611e76069970adc7ed6f5e5e1b01397a8e