Malicious PDF — malware analysis report

Static analysis result for SHA-256 33726408a27158f3…

MALICIOUS

PDF

86.8 KB Created: 2021-09-12 08:10:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1aca295e2c1680862cfe7c9b35aad4c4 SHA-1: 4569f971728687fa30a0175e4a4a38aee3f60cce SHA-256: 33726408a27158f384ae7e2929dad860ef064e998febb41d6662b934a48eea53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit users through these links, potentially leading to phishing or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://celcg.pl/uploaded/file/gofumosajeli.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/8b1b10f56cf547cf6a87d08f252d17b0/metomarowu.pdf
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16138df1c39241---58676566171.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613642f417156---boziwavuxogin.pdf
    • https://mimpisiluman.com/contents/files/kanimifebakedalox.pdf
    • http://redskap.ru/userfiles/file/wodigutijomanolozem.pdf
    • http://dulichgiahy.com/upload/file/lunojumanazekabeno.pdf
    • http://jgweld18.com/UploadFile/file/20210907090246014.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613af435aad53---8651130588.pdf
    • http://riskhedgetech.com/uploaded/file/417605185613a9e76d9de1.pdf
    • http://statsale.com/data/upload/ck/files/72704259689.pdf
    • http://vagyonvedelemszolnok.hu/admin/fck_upload/file/godurorunu.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/7eb143754fa03083c7c015c73371c679/85840216865.pdf
    • https://redengewinnt.com/userfiles/file/92554068095.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/9e47b30dd9cf6ddb2a95974e5aec6819/36432221750.pdf
    • http://vasekurzy.cz/userfiles/file/setumokaxipatase.pdf
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/2506133838.pdf
    • https://ego-sofa.tw/uploads/files/202109040245325747.pdf
    • https://www.thic.net/plugin/ce1/ckfinder/userfiles/files/55771241402.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/844e67f7beef065db3bb5cd52eaf93b0/kobegineruvalobujik.pdf
    • http://softwaretesting.kr/club/data/userfiles/file/20210912042051.pdf
    • http://www.slenderclub.cz/ckfinder/userfiles/files/nevadefajupulamomukura.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb8225ee4b---80391083617.pdf
    • https://www.sistemkabin.com/ckfinder/userfiles/files/34164846684.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=free+gameboy+games+for+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0b7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B7 16792 bytes
font_01_sfnt_off000108ce.bin
1fd44a3c451786e367b0811b19c243c1c31fd7e94d9f28719787188b7f5f4e0e
pdf-font-stream PDF embedded font (sfnt) at offset 0x108CE 10784 bytes
font_02_sfnt_off00012161.bin
8b11d5a1dcec97162a44a5c0831e72ed708d380cb572d2c56a5b5a71c3e2e738
pdf-font-stream PDF embedded font (sfnt) at offset 0x12161 17024 bytes