Malicious PDF — malware analysis report

Static analysis result for SHA-256 c79d1f8122c291cc…

MALICIOUS

PDF

76.5 KB Created: 2021-04-19 02:55:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 151114fdfc7526317f54080f9fc42f00 SHA-1: 200b864ae39f9b5e4b6527a6504a014ef8f21bfa SHA-256: c79d1f8122c291cce38d383ec7e386bc01d361166138ef937b8dfa878fc8fb0a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to seemingly legitimate domains but are structured to host malicious content, indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic. The document body, though heavily obfuscated, suggests a lure related to printer setup, which is a common tactic for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://www.pbttphtk.gov.my/sites/default/files/webform/nolukaronedibikix.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/49323480199.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/48862039041.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/pulipalukegibivep.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/fifomibap.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/17947704001.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/monufugabezexi.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/mulakipezumaxusilexuvu.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/95374483905.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+setup+airprint+on+canon+pixma+mg3620PDF link annotation
    • https://campusrec.princeton.edu/system/files/webform/93394875634.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/9071701793.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://scripts.sil.org/OFLIn PDF document text
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCAF 5932 bytes
SHA-256: 761146162d0e7768e065355c5d8ec3fc2c8ce132c3d911d023178584c4e6c462
font_01_sfnt_off0000f0d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D8 6068 bytes
SHA-256: d8e4b7f44dfb66ea49c7f1cefd345a391fade3fb548cc17de4cdbf151663dabd
font_02_sfnt_off00010089.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10089 10628 bytes
SHA-256: 758253b9e6e1d1108c4dba10fbdd0df452d145834bf21c194895f509c5ecd362