Malicious PDF — malware analysis report

Static analysis result for SHA-256 50c7972a8d3b96eb…

MALICIOUS

PDF

73.0 KB Created: 2021-09-18 17:43:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f060008533f1cc7827ff34986c42cef1 SHA-1: 845238f036e0c131d478c467dccd993414a3294a SHA-256: 50c7972a8d3b96eb819a44b7330dfb370fcab6ab92aaf8cb814ca652960c6514
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The file's structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://archism.ru/uplcv?utm_term=install+button+not+working+android PDF link annotation
    • http://wyadonline.com/userfiles/file/rapokuz.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/61664119896.pdfIn PDF document text
    • https://nikolsbeauty.com/webroot/f/uploads/file/33081098078.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d0467b685---luxibelim.pdfIn PDF document text
    • http://agppi99.pretty-match.com/upload/files/20827477470.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/zebidosinepatalaten.pdfIn PDF document text
    • https://corpeverest.com/ckfinder/userfiles/files/92800258196.pdfIn PDF document text
    • http://pinxedien.net/upload/files/xamasojedif.pdfIn PDF document text
    • http://lgassociates.in/uploads/6901100201.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/76114155140.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/27151618576.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/161374d0bb06b2---darawononazizukodubafi.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/lozemalo.pdfIn PDF document text
    • http://cabanagarden.hu/editor_up/jikijajugodozevis.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/33396106514.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161306995b0f5b---41033141667.pdfIn PDF document text
    • http://gevenschoenen.nl/ckfinder/userfiles/files/puraxaborulevaxakexevig.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/e06a3f01e824bd4db90e5fc1396bfa88/71044184244.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/88127084166.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210904060459.pdfIn PDF document text
    • https://warungmimpishio2.com/contents/files/tibigigurekolulojor.pdfIn PDF document text
    • https://www.luxboss.com/ckfinder/userfiles/files/30927296435.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_off0000b9a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1B4 17248 bytes
SHA-256: daf965a0407f29990c5ea6a051d6cf651ef76ea37069e7091356f1e90b8c74ce
font_02_sfnt_off0000fe16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE16 10660 bytes
SHA-256: c099ee1ce02af19c8506355bde8546721fa2decff3b68186d911cce1f86877e3