Malicious PDF — malware analysis report

Static analysis result for SHA-256 87ec8b102ff7b334…

MALICIOUS

PDF

82.4 KB Created: 2021-09-19 14:13:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4167213f3ee1496990b018f9737c2a4b SHA-1: 4999f7083663f9277b16ce2315fead792d77b2c2 SHA-256: 87ec8b102ff7b33498e52079edf78b2fe6a5b49abcffd4511063a158d91c310c
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains a link farm pointing to multiple compromised or disposable hosting sites, suggesting an attempt to distribute malicious content or phish for credentials. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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 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://specializedfacilitymgt.com/public_html/userfiles/file/67562497473.pdf In PDF document text
    • http://agarimo.com/archivos/archivos/40342224588.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/mukiwo.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac79668731---25938779672.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/1905239973613cc2808d214.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/2924253f67b8b82d1a17fd79b8f99c12/zegidowexufajutijipo.pdfIn PDF document text
    • http://raffaelecavazzoni.com/userfiles/files/9627391493.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/87201081165.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/gibebevoretixewulaguzu.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/14839462432.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163114872791.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613247853de8f---86756890540.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/74126226343.pdfIn PDF document text
    • http://beiks.info/public/file/85115197580.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/2gnvd47a6kdojvpgmgp2nfsa99/87760869516.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/lijunu.pdfIn PDF document text
    • http://xn--80aantfcaehjbxzf1m.xn--p1ai/userfiles/file/9819519359.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/nofoxomukakeguput.pdfIn PDF document text
    • http://marchmont.ru/imgs/file/14608266874.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/77802119138.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161411c90e5580---88458299511.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/99588493158.pdfIn PDF document text
    • http://nenorm.com/files/files/89462409231.pdfIn PDF document text
    • http://chicopharm.com/upload/files/xabofurekadigiraxufit.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/8c2a9fdddafc1a6795249aa9a6edc075/375263562.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=winning+eleven+2012+download+appPDF 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_off0000db2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2D 18764 bytes
SHA-256: 4718712f38737ae5cb5756d20304f54e5cec260c0dce01d4abe0e417ccfec110
font_01_sfnt_off00010bbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBE 10640 bytes
SHA-256: 06fa26335c24458523f8b773066c079b39b13f22df6217ce8f30660edc6c830b
font_02_sfnt_off0001240c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1240C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1