Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a53e0774e2a84fd…

MALICIOUS

PDF

70.7 KB Created: 2021-04-13 06:44:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 0ee39372a80ddad9e8d7f2e1b6d7b20d SHA-1: f49a99dd867f364171ac3fa7c776ffe3e202f9fc SHA-256: 0a53e0774e2a84fd2029e8fc35d2c08acf96b014c14b36510edd87e8e13d262a
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 disposable domains and are structured as link farms, a common tactic for distributing malicious content. The document body, though heavily obfuscated, suggests a lure related to 'Auld Lang Syne sheet music', which is likely a pretext to disguise the malicious intent of directing users to these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.enwidth.com/sites/default/files/webform/resumes/60015669747.pdf In PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/41266633523.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/wokasonexigugeb.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/10654010608.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/topijetidilotifoga.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/xufatonapa.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/vopezupudatirarib.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/89533113822.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/gurolaxi.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/pifudolaloxafedotodela.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/lavajaruzapelusudixavu.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/21691652676.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/4264017636.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/bulurifabisiwotubavigivos.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/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=auld+lang+syne+sheet+music+with+chorPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/67925993666.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD911 5536 bytes
SHA-256: 6c005e2306d25c982eeccef11e613a95a42e408f41862932be7bee3a16f08502
font_01_sfnt_off0000ebcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCD 11040 bytes
SHA-256: cc241ef3b821b1e0a11ea381f687647156bd469000eda1f55265757fb2e704df