Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce8838a4f1f65603…

MALICIOUS

PDF

76.2 KB Created: 2021-09-05 17:26:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9573d1d649dbe49185fc57b442defeac SHA-1: f12889bc4c40ba3480d83c9dd59c8fc722473855 SHA-256: ce8838a4f1f65603c14bb7951333884740d9fc078bc98affdeeb04eb5bf21679
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains or compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chcial.ru/uplcv?utm_term=indoor+cycling+training+plan+pdf PDF link annotation
    • http://kukubara.com/zdjecia/file/biligomesovuroraxa.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/paxorolazetepilolawomu.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210511171857.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/1776420330610a0ef8aae84.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbbee4aa58---5750478301.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/f6f2eae46de632a6fcfc3822a7d8fba4/78825252573.pdfIn PDF document text
    • https://benhgout.net/uploads/Files/file/vixogekiguregufafe.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/87188580307.pdfIn PDF document text
    • http://munnarinfo.in/userfiles/file/xufil.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/zebokolasusisuzosokono.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/vojobav.pdfIn PDF document text
    • http://xdata.pl/app/webroot/img/ckf/files/damemotanilotolek.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/23225899335.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/76907011002.pdfIn PDF document text
    • https://jv-cms.crazy-jessie.nl/uploads/files/16579139418.pdfIn PDF document text
    • https://lawtutors.co.uk/js/ckfinder/userfiles/files/60017680749.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/46277606977.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/075ef9942662e07b7a20062229be0064/dugevo.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c63604aca0f---pefosikogufoniwonebivovo.pdfIn PDF document text
    • http://hillandcunnreunion.com/clients/864369/File/74344332904.pdfIn PDF document text
    • http://lso-msm.fr/userfiles/file/jofozotuxex.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/75461724719.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_off0000c59b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC59B 17504 bytes
SHA-256: b8d66b64c4a7cff87a3d2558154f51338c32fb99b7df42287b4e9c31370403a0
font_01_sfnt_off0000f32f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF32F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B46 10560 bytes
SHA-256: 9e1f154b1361966dc06add82f5479fd5c78ce6a08b81d87923e6c4008ce7ed35