Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c113af536140d5…

MALICIOUS

PDF

77.6 KB Created: 2021-04-11 15:36:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 2dbf2879046c2a9f2bea5423e7d5a709 SHA-1: 5a8bfd0ad9b50c2458c4fb62e63c961e4035d1e3 SHA-256: 99c113af536140d55b5f8fb2bed02f9ac511feb1fc09b084e6296c5bdb178535
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or link farms, suggesting an attempt to obscure the final malicious destination. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a likely phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.uts.cw/sites/default/files/webform/xewaz.pdf In PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/wefegazeketalewawer.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/17184396690.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/72664382884.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/banofamuwidobekoke.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/xubapubawaral.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/13178745316.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/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=stanford+binet+intelligence+scale+5th+edition+pdfPDF link annotation
    • https://campusrec.princeton.edu/system/files/webform/26909318775.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/4167827641.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/jelozubunumi.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/45540448673.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://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_off0000daba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDABA 5784 bytes
SHA-256: 6f22abe035a8d6ed2f33116fe60abc2a31ef7536bff7573ebae91c9ed7a2c1cf
font_01_sfnt_off0000ee65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE65 10876 bytes
SHA-256: 80c28dd74034697779238ea557da10675db6eb51fd8b9d918de4f42361316c68
font_02_sfnt_off000113c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113C8 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501

Open this report in the interactive analyzer, or submit your own file for analysis.