Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4b2c1b78f1f33d2…

MALICIOUS

PDF

73.5 KB Created: 2021-04-12 09:02:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 68fa6c36a9c7f55fa0bcde660860103d SHA-1: b47c081ddd7abb7030ca20b949a385dc79ff49d8 SHA-256: c4b2c1b78f1f33d27f64cd87e4c36adacf4e38935b4627f0bb1aa42ced7a92e3
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 high likelihood of malicious intent. The document body, though heavily obfuscated, suggests a lure related to 'Fisher Price Rainforest Jumperoo instructions', likely a social engineering tactic. The presence of numerous external URLs, many pointing to disposable domains or link farms, further supports a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://cicatsalud.com/html/sites/default/files/webform/25507329945.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/67198091979.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/17184396690.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/sizewavajifur.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/jalipoxelelikepobolid.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/nukuromenalifaru.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/57515461030.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/77599308563.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/76938035167.pdfIn PDF document text
    • https://www.afscme65.org/system/files/webform/52844377902.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/dakatiwilu.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/DOqCt-cVA4I/uplcv?utm_term=fisher+price+rainforest+jumperoo+instructionsPDF link annotation
    • https://community.princeton.edu/system/files/webform/xakefabobadu.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/luzixuganigofifabeja.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/56381184371.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_off0000e131.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE131 5252 bytes
SHA-256: 136967abfd344a582583625dde3751fe808814fe2466562bd42a45f94f55b866
font_01_sfnt_off0000f2f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F3 11140 bytes
SHA-256: da950c589e81ad1aacd4a0c69d5839f53a6d34ea83595032ab7e61c374734195