Malicious PDF — malware analysis report

Static analysis result for SHA-256 27b165299dd0c4e1…

MALICIOUS

PDF

74.4 KB Created: 2021-04-20 09:46:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 420f8e403da101d432231b31bccc2423 SHA-1: 1a1f6d598066c93f27adcd71e7946eaccc12c551 SHA-256: 27b165299dd0c4e1a483d8e9ad1317346e140f1dc5236698dcb5a53fac731fc1
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to domains that appear to be used for hosting malicious content or phishing lures, disguised as legitimate document uploads. The presence of 'risd academic schedule' in the document body suggests a social engineering pretext to trick users into visiting these sites.

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 https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/ratasivovo.pdf In PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/74296331991.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/bujepalifomi.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/tesogiruzan.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/xugapovapoz.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/nolukaronedibikix.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/61975266633.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/61928937085.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11364316539.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/17423244846.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/25507329945.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=risd+academic+schedulePDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/54002061309.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/50156150340.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/jawugu.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE590 5088 bytes
SHA-256: fb0c96a7f94a5f5f8592fb636301741bb7fedacf0ffdc46d911043cb30a60511
font_01_sfnt_off0000f6bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BF 11120 bytes
SHA-256: 6434cc1642a144a07a079794d6b4b9b0aeac0208fed2a1415482a545a310c592