Malicious PDF — malware analysis report

Static analysis result for SHA-256 57ec4e9624d03bec…

MALICIOUS

PDF

77.2 KB Created: 2021-09-30 10:48:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5d8c5a20b45c157b6a9d723e541e1d1d SHA-1: 791f2d03f5eb3a8756701b24f50eff8cfd98dfd0 SHA-256: 57ec4e9624d03bec5448093c698cccb55668f83154512e1cbd023b108c05edac
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to host malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://sarkar.ie/userfiles/file/3927692914.pdf In PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/66610784294.pdfIn PDF document text
    • http://spellenindex.nl/images/uploads/galig.pdfIn PDF document text
    • http://www.puhito.hu/uploads/kilimujomenazuranajuru.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/56cbf323fe43ad4b219d28699d8ad574/63728850899.pdfIn PDF document text
    • http://tunapvietnam.thietbiotoviet.com/Images_upload/files/3277034394.pdfIn PDF document text
    • http://vektor28.ru/userfiles/file/menibizekonakaloweju.pdfIn PDF document text
    • https://seerupit.dk/assens/file/59227109022.pdfIn PDF document text
    • http://ahzgbh.news-read.com/upload/files/timekasosesawakokejaki.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/leginofusep.pdfIn PDF document text
    • https://termokingbt.com/ckfinder/userfiles/files/60887296530.pdfIn PDF document text
    • http://falegnameriacastiglione.it/userfiles/files/55365944867.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/sopesojo.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/85095708665.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/46bb9b27fcdf8df34143cf3f19d76b8f/45877471084.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/95333857694.pdfIn PDF document text
    • https://next-engineering.com/userfiles/files/21513889841.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/tavafetifid.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/s73lcbe33oj9sk2mqmbbcbrs8o/tidogemipisiwa.pdfIn PDF document text
    • https://hse.tw/upload/file/7122986504.pdfIn PDF document text
    • http://techmechengineers.com/uploads/54033874790.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=office+365+mail+server+detailsPDF 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_off0000bf75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF75 10980 bytes
SHA-256: 0a251a658349adde983a6f1ee21df2993008a5d6a984f07727332d65d09793b4
font_01_sfnt_off0000d913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD913 20624 bytes
SHA-256: 4e42cf682d3065045ca067500a0bd4870dc717a5f1542f413d69a4ffd2a8c60d
font_02_sfnt_off00010d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1