Malicious PDF — malware analysis report

Static analysis result for SHA-256 a21386c3a95ae139…

MALICIOUS

PDF

67.9 KB Created: 2021-09-30 22:04:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ac52d10fcb83b6138c66108f9de6444e SHA-1: ea4cb20259ade09bfebdc382737a481a1f230baa SHA-256: a21386c3a95ae139e90fe132be55f84bda100f368af77c865d297d975c8eb292
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or are part of link farms designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to lure users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://smidgel.ru/uplcv?utm_term=cheapest+smartphone+2020+philippines PDF link annotation
    • http://doorsatyrau.com/ckfinder/userfiles/files/34081834961.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/jidawovibuveladered.pdfIn PDF document text
    • https://gkia.org/kingkong/userfiles/files/47527848612.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/8967013763.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16135264c47441---woririsatogajaloxinerado.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/5855538568.pdfIn PDF document text
    • http://formacio.fic.cat/uploads/file/xupog.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/9508cf3b38d0f8451d0deb9d2287ec5f/midosadu.pdfIn PDF document text
    • https://alutat.com/data/file/58845766581.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/lukufuzimavili.pdfIn PDF document text
    • https://zhansq.cn/upload/file/kedutitaboditadokid.pdfIn PDF document text
    • http://chatyzvule.cz/uploads/13381998624.pdfIn PDF document text
    • https://gsacademy.ge/uploads/files/70054276642.pdfIn PDF document text
    • http://happyorderfood.com/uploads/files/wesevopimusenevekorewuzo.pdfIn PDF document text
    • http://chaputlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/8186517476.pdfIn PDF document text
    • http://spharma.ua/files/file/mowezutemip.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/pimodelusaxovodujadobi.pdfIn PDF document text
    • https://mimpiindah168.com/contents/files/91957061993.pdfIn PDF document text
    • http://pointerboards.com/uploads/admin/files/22321543000.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/37177878089.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210924_081125_2134.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613e2ed61e9f2---23562542909.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_off0000aca4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACA4 10788 bytes
SHA-256: dbd222de87563118ab3179a436e1188acf80d4f34e270a9bf23b5a58472fab50
font_01_sfnt_off0000c557.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC557 14696 bytes
SHA-256: 7b6f91925c6d03db2b7b82b862b3933eaeb45deec462195c471f7094c31f8952
font_02_sfnt_off0000ea23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1