Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1b4bba8f739fe77…

MALICIOUS

PDF

78.6 KB Created: 2021-09-18 07:52:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 94c4615e487e2e7883b1d29db79e5807 SHA-1: 9a4abd18f02bf60f4e256e89339d3ab5d74d191a SHA-256: b1b4bba8f739fe7773f4f38e1dc2022cb1de0948fa45ed3aa3f1559c53032691
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple external URIs and link farm indicators suggests the primary goal is to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://synerhu.ru/uplcv?utm_term=swift+streamz+latest+version
    • https://clubesolbra.com/uploads/files/52312012896.pdf
    • http://pmke.cz/pictures/files/19101239298.pdf
    • http://indagosrl.it/userfiles/files/poked.pdf
    • http://rymwid-training.com/userfiles/file/xugur.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/a050fc9ae51a2da7d9e0521b8f9aa81b/38924201800.pdf
    • https://padservhosting.com/userfiles/file/jajetokalovagegusanilapa.pdf
    • http://hfengly.dk/skoleportalen/userfiles/file/3811931508.pdf
    • https://penzion-pod-rozhlednou.cz/img/file/serivawawilemiv.pdf
    • http://hastensandbreakfast.nl/userfiles/file/tigujexage.pdf
    • http://phuclocvienjsc.com/uploads/image/files/43922475860.pdf
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/9759770406.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161403329de3f7---nelow.pdf
    • http://rtm-plus.ru/ckfinder/userfiles/files/45991029634.pdf
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/88550893524.pdf
    • http://vincitydata.com/uploads/ckfinder/files/xarawamalivemijagugokesag.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/5de4afeb46d7c235f68d039b96f58c39/mapuwedixeguvekari.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16140e41c886d9---72653163754.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/0a1853d8ace12635dc11fc7b8ed6ff86/7745675227.pdf
    • http://mamolenasnc.it/userfiles/files/nokiw.pdf
    • https://pnvvr.ro/userfiles/file/13131563433.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/75bdaf691d11760cae97995591e7994e/zewivu.pdf
    • http://bm-shower.com/userfiles/files/puxajenugixapunax.pdf
    • http://vocal.bpv.su/content/files/files/27831341791.pdf
    • 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_off0000cffb.bin
96416058ca86430edaeec83337a929070fe5f2c28392734364fc5992c0c165b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFFB 10660 bytes
font_01_sfnt_off0000e877.bin
b6817f2631f38bfa3ca29235cb70dc64bc53dac15372ec557b872b5ac60517f4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE877 17160 bytes
font_02_sfnt_off000114e9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x114E9 16792 bytes