Malicious PDF — malware analysis report

Static analysis result for SHA-256 193cfc75e778e715…

MALICIOUS

PDF

72.5 KB Created: 2021-04-14 03:56:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 81269138ee0cd39113e5bc7817d1b257 SHA-1: bae750b13767c0f3c9e9ff2d879e4ceacbe667e6 SHA-256: 193cfc75e778e71575ab7a9f88d17a494ed48f409c3bd93721d3fbfbd6f1e98c
134 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.jwico.com/sites/default/files/webform/41164207556.pdf In PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/bidepe.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/sojivezogi.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/bofuwidesuxugebogaxa.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/vojowavujelosapol.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/zateguzafafidefezibexe.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11118021720.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/bukitonixoravutewoluba.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/pagijan.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/72664382884.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/kafavepovimurajubek.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/vobefoxejajizagosoberob.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=pdf+lined+paperPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/87767597376.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/kizoromafogikigogusebef.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/60395266702.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/fapivo.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA3F 4456 bytes
SHA-256: 93faa91c1a920fc151add7588ae8d01d9e3afbc4f89bbc3d3fa70bb6958952c2
font_01_sfnt_off0000e952.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE952 10180 bytes
SHA-256: ea2b4423394f9734f4dc1d16cbbef5d04c70f97937d1720bb37fe51041cf110b
font_02_sfnt_off00010c31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C31 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176