Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cbcc0d311f5354f…

MALICIOUS

PDF

75.7 KB Created: 2021-09-21 05:01:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 28c317678e14b4667cda4d56542b396f SHA-1: 382973d00d31f8f271dbced20fc51d3bc422861a SHA-256: 8cbcc0d311f5354f16293342cef12c1e6bebeccecb5a8972941547268a4dc579
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous external URLs, many of which are hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded URLs indicate an attempt to redirect the user to malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://philabc.ru/uplcv?utm_term=xiaomi+tv+chrome PDF link annotation
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/jumati.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c6cd50313---17889374910.pdfIn PDF document text
    • http://scantech3d.com/files/kupumewiresej.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/wenosifuk.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/81533f0b7337bf195beb2f74403fd86c/todoga.pdfIn PDF document text
    • http://www.udelimpa.es/ckfinder/userfiles/files/38143162212.pdfIn PDF document text
    • https://jxlmedu.com/file/files/20210919_150419.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/gokaxasovonijufoliretaz.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/pemexaxadunorutipagawa.pdfIn PDF document text
    • https://institutdesante.org/userfiles/file/wepukuditaturimumij.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/kegixabirow.pdfIn PDF document text
    • https://angkalaris.com/contents/files/2243034997.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/zifinugedezokuvexok.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/9e82ac685078a36193055ab555b8f2c7/31375283888.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/6988895315.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/e768051aa7ae8cf9a1b415d1236f87ac/60603736315.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/99757210104.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210912044634.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/19330320434.pdfIn PDF document text
    • http://labotinnghia.com/img/files/vefikuxa.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/26462791073.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613023037cdfe.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_off0000c650.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC650 17264 bytes
SHA-256: fffc038e7253d76e71faaf7835da0c422d036d05f79149278cecdaee407c332e
font_01_sfnt_off0000f289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF289 10248 bytes
SHA-256: 1c389e6ec637b0dedabb31de903d712999ece61ef406cc0b4feebf022fb458ef
font_02_sfnt_off00010997.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10997 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1