Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff31344cdd1930d7…

MALICIOUS

PDF

71.0 KB Created: 2021-09-26 00:04:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: dec1eeb8f03dc363d520fb8c8cc8f109 SHA-1: 3c78114f8dda5b10c0492d1b3a8ea79b373536e6 SHA-256: ff31344cdd1930d7125f2592bf1f4eece2dd341f04f823014db4d8b237cdf37c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it's a link farm pointing to compromised WordPress uploads and disposable hosting. The PDF contains numerous embedded URLs, many of which are likely part of a phishing or malware distribution scheme. While no scripts were explicitly extracted, the nature of the embedded URLs and the 'link farm' heuristics suggest potential for JavaScript execution or exploitation to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://laborke.ru/uplcv?utm_term=fox+bet+android PDF link annotation
    • http://ceskylakros.cz/userfiles/file/risilabugubo.pdfIn PDF document text
    • http://kgmda.com/upload/files/rufojo.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/6ov5i2rnmug5se5i9sufjhkj6r/28738552044.pdfIn PDF document text
    • https://corcreation.twbiz.me/data/fckeditor/files/20210907_012503.pdfIn PDF document text
    • http://www.heksan.com.pl/file/30561209252.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/28424260535.pdfIn PDF document text
    • https://alquimia.in/admin/fckeditor/editorfile/79298340194.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/roxixik.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/f318a535e920ea42db2872b5491bcef4/21178614883.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133edc6ebdd2---47093772287.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613248925b584---kenosugejigufasibit.pdfIn PDF document text
    • http://grappin-annat-como.com/userfiles/grappin-annat-como.com/file/xefepupisoxuneguveburiwa.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090110480248.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/23076944169.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/34421557513.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/dudetenimileniroxa.pdfIn PDF document text
    • http://phupmirpol.pl/userfiles/file/4080894563.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/25836274909.pdfIn PDF document text
    • https://www.suep.gr/ckfinder/userfiles/files/jasedamo.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/47833145991.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/burugedukuzejikuwemalok.pdfIn PDF document text
    • http://offerparts.com/upload/files/8792162808.pdfIn PDF document text
    • http://openendrep.com/userfiles/files/78881096095.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3613a3421---bipegibaforitosirufovemu.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_off0000b2b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2B0 17444 bytes
SHA-256: d5e87f8dda01791ee4a03652b068017364733bfd782b5248f6fbd1e3f10121b0
font_01_sfnt_off0000df8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8A 10244 bytes
SHA-256: 21c7a0b92caa8b43f3b1f8f3bab2177e08dfe5075d1d88934fea7539e70425fc
font_02_sfnt_off0000f6ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.