Malicious PDF — malware analysis report

Static analysis result for SHA-256 85f9697941a28f41…

MALICIOUS

PDF

75.3 KB Created: 2021-09-28 15:14:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f59c17c89551557abac12059b974b4f0 SHA-1: c7a26535e9eb4b6e68678c7684e997c3c1436d31 SHA-256: 85f9697941a28f41948452cf6e5b4af2b8733ac152d1d42b715a39235d4c63ae
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs and heuristics indicate it functions as a link farm, with several pointing to compromised or disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the document structure and URL patterns are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://archism.ru/uplcv?utm_term=get+followers+boost+apk PDF link annotation
    • http://le383.com/uploads/files/kevafat.pdfIn PDF document text
    • https://penzion-pod-rozhlednou.cz/img/file/71026621713.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/47399834292.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210921_28BD7F6C9B35DBD8.pdfIn PDF document text
    • http://odontotecnicacoop.it/userfiles/file/zuxelolasiwotat.pdfIn PDF document text
    • https://magerp.org/upload/files/25344456494.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161527e85d0eed---80511067469.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/kisosavetovemusokipile.pdfIn PDF document text
    • https://www.mmgrowersg.com/ckfinder/userfiles/files/58443715835.pdfIn PDF document text
    • https://lacausedeslivres.com/userfiles/file/26290449101.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/7205386665.pdfIn PDF document text
    • http://anpharma.net/upload/files/17521830304.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/8b1f1a27786d52ca5dcf8fddae33eac8/zuzifakojus.pdfIn PDF document text
    • http://mh-gartengestaltung.de/userfiles/file/rapozimajobu.pdfIn PDF document text
    • http://jsushibrea.com/uploads/files/wugeterupaben.pdfIn PDF document text
    • http://motolargo.pl/userfiles/file/pusovededusupusaji.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/jiximu.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/lufefa.pdfIn PDF document text
    • http://gelinyuanyi.com/upload_fck/file/2021-9-17/20210917161507504231.pdfIn PDF document text
    • https://semsaesp.com/ckfinder/userfiles/files/62443397051.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/tafukopufixu.pdfIn PDF document text
    • http://nexxstep.nl/userfiles/file/89333571786.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e8aef2cf3---76784428157.pdfIn PDF document text
    • http://ginzaoakland.com/uploads/files/pukoruferavituzasofuzosex.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_off0000bca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B3 18968 bytes
SHA-256: a41ecf27eea6177c029aa5ebd0216a0eaac288f7824aa94599292686309f401d
font_02_sfnt_off000105fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FA 10512 bytes
SHA-256: 634abf5228a3f7f3c5fec8e2901bee9468722fe3f63d63567246651c263c817c