Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6873aa7c120ba35…

MALICIOUS

PDF

68.6 KB Created: 2021-04-22 11:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 0e0382b9e51560d66cfb9f602485a54c SHA-1: d24b14d5892a1f15e43a05a3c2084794f3a183c5 SHA-256: d6873aa7c120ba35b50fa4845923a345ab14acb622db30ec10cf1fe9fe7bbb5b
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 payload. The document body, though heavily obfuscated, contains references to 'Troy bilt tuffy tiller manual', suggesting a lure to a link farm. The presence of numerous external URIs, many pointing to disposable domains or link farms, further supports a phishing or malicious redirection scheme.

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://www.mothercare.ro/sites/default/files/webform/resumes/jilagofuzepev.pdf In PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/27017481005.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/mogewewe.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/71048230710.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/dufadurelabakugozuku.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/rijuluzevowogadabiwi.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/89737617204.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/welukugipevodabarovefeweb.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/vetasitumuwogemukuruv.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/28693943460.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/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=troy+bilt+tuffy+tiller+manualPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/jawugu.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/85064040694.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c4ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4BA 4808 bytes
SHA-256: e7bfac5f45f9a563ff8687a146d30637c336037f0b8db58f729541123f5b8315
font_01_sfnt_off0000d4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FC 10180 bytes
SHA-256: 00e856e713f9f474f6796c9dfaae83bbe321f56f2d19960b3f5bb8defdefdedb
font_02_sfnt_off0000f7b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B6 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378