Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcbb6fcb19391942…

MALICIOUS

PDF

75.7 KB Created: 2021-09-21 07:34:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3663c322d3af875fb1670cd4d622a618 SHA-1: 1fc895ddf68eb0acab68f1910e8be33b3e8f12fe SHA-256: dcbb6fcb19391942fcf39ff31aa54d87c809f9eee603e5333669124f900f3ed3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. It contains numerous embedded URLs, many of which are hosted on disposable domains and utilize UTM parameters, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded URIs indicate a likely phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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=fortnite+android+apk+2021 PDF link annotation
    • http://amsasecretariat.fr/userfiles/file/fowogeb.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/37972307327.pdfIn PDF document text
    • http://staropolski.net/Upload/file/85723793796.pdfIn PDF document text
    • https://www.nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/viletinifojalimurasab.pdfIn PDF document text
    • http://aburobocon2019.mnb.mn/uploads/files/ninileko.pdfIn PDF document text
    • http://namlinhchisapa.com/userfiles/image/file/padobazowuf.pdfIn PDF document text
    • https://paeonia.ch/userfiles/files/83673885748.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/88367106350.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/zusadale.pdfIn PDF document text
    • http://lobi.md/userfiles/file/95892131704.pdfIn PDF document text
    • http://asirakademi.com/resimler/files/rovibesejibabon.pdfIn PDF document text
    • http://fabiocaronearchitetto.com/userfiles/files/bodifusimubada.pdfIn PDF document text
    • https://nbretail.com.vn/ckfinder/userfiles/files/vibivitex.pdfIn PDF document text
    • https://hsse.cl/files/moferavaruzimo.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1631398656_1191391126.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/58257148337.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/jazobumunu.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/mubetalilekuvo.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/43545849980.pdfIn PDF document text
    • http://bosch-elektronarzedzia.pl/catalog/file/9036873966.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210917_0109B4FC8BD1ABA1.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/7799198686.pdfIn PDF document text
    • https://hiperaktivite.info/userfiles/files/41509098225.pdfIn PDF document text
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/31888464251.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_off0000c2d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2D5 10536 bytes
SHA-256: 3847a3b3afcd5cc001ae21104f50288a947956913a104341bfce79edb7272f61
font_01_sfnt_off0000daeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAEB 17792 bytes
SHA-256: 36f7af78cc991af3720bce5e251eb843bfa7765548a95a46caf09458f343a5c9
font_02_sfnt_off0001096e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1096E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1