Malicious PDF — malware analysis report

Static analysis result for SHA-256 8596ed34917f78f8…

MALICIOUS

PDF

72.3 KB Created: 2021-07-18 19:37:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 33eb60200573e46cbc18d9d0f15b0c48 SHA-1: cc06cca17e3c30a7481ca3c036683320e635b94f SHA-256: 8596ed34917f78f8a6ea945939232bf918204daba2a0bf5c1a745784693f5dd2
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the nature of the embedded links and the PDF structure point towards a common technique of luring users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607c77737858a---ruxamawimoz.pdf In PDF document text
    • https://larrialdiak.es/files/galeria/files/73821270268.pdfIn PDF document text
    • https://cafepiolho.com/uploads/assets/kevag.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/trju4rhq6foqoo09i2ejrbl0c4/58539490533.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/7efed86fd92715571a0cd8d8d57071e8/8924073133.pdfIn PDF document text
    • http://brightwayconsultancyservices.com/userfiles/file/66327265649.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d662e98288c---81203146405.pdfIn PDF document text
    • http://thumpamonpally.com/userfiles/file/95836323397.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/tikiwitofokaw.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/xibixos.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/68485964852.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-2/20210502005630587742.pdfIn PDF document text
    • http://flambotour.it/themes/userfiles//files/42057565243.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160857da04e442---xufipotawar.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/xonegagugesokunaruresuzus.pdfIn PDF document text
    • http://westtech1963.com/clients/d/d4/d4250bc21dcbbf02d7f9bc68df143add/File/31850871447.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/b8087df08233ecbd14e74b6b56d989a6/20516853127.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16098564e442bd---57991673057.pdfIn PDF document text
    • http://reklama-kemerovo.ru/files/files/wevav.pdfIn PDF document text
    • http://seednseed.com/admin/fckfiles/file/zegewegezilusikuvik.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160d7e9472cb8b---11915582565.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160776fe2f3901---77672100991.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/natodagedobujudemojibanu.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4ffdb094b---lokukutadodogedula.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=black+administration+act+28+of+2005PDF 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_off0000ba83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d29a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD29A 11236 bytes
SHA-256: ac642f7d3589c1da686d6e843704d3ca2029f981d21d87913f2674a9c0c6e567
font_02_sfnt_off0000ed00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED00 15076 bytes
SHA-256: 5bb69f5ef8b0886dde678cf8c389f5ff3c1b7c995830380b4a35eba196e30f51