Malicious PDF — malware analysis report

Static analysis result for SHA-256 77f21720ce45e3e3…

MALICIOUS

PDF

65.3 KB Created: 2021-04-22 10:32:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6d0aa2c881397401b10786c0a7b2c1e SHA-1: 1ff0f017bcc7f9966fcc0a285fb070710c7d1d76 SHA-256: 77f21720ce45e3e3d49c654533708b90822b054032fd6d5242d8d8e39f1ecb31
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. While the document body is heavily obfuscated, the presence of many external links suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8526

Heuristics 4

  • 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
  • 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://architecturaldesigninc.com/sites/default/files/vudezuluxi.pdf
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/14219433733.pdf
    • https://natsihwa.org.au/sites/default/files/webform/80931084074.pdf
    • https://www.natsihwa.org.au/sites/default/files/webform/setafemamuf.pdf
    • https://www.enwidth.com/sites/default/files/webform/resumes/89382212171.pdf
    • https://www.afscme65.org/system/files/webform/tikat.pdf
    • https://www.jts.org.jo/sites/default/files/webform/wijuwimitixatedus.pdf
    • https://www.enwidth.com/sites/default/files/webform/resumes/ziwisotug.pdf
    • http://portal-mysigma.com/system/files/student-proof/woximinel.pdf
    • https://www.a1touchsolution.nl/sites/default/files/kobovigub.pdf
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/falaburisidibiwad.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=twilight+saga+new+moon
    • https://lib.asu.edu/system/files/webform/56381184371.pdf
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/60395266702.pdf
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/vifixofixif.pdf
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/pitoripizebareko.pdf
    • https://thesanfordschool.asu.edu/sites/default/files/webform/83703622856.pdf
    • https://community.princeton.edu/system/files/webform/xakefabobadu.pdf
    • https://thesanfordschool.asu.edu/sites/default/files/webform/85266863194.pdf
    • https://gradfutures.princeton.edu/system/files/webform/25860956451.pdf
    • http://scripts.sil.org/OFL

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e460.bin
0ba7b94c5ccdb05c8b17ff3e994f3ad2d763db5aac3961508a3965839b59bf84
pdf-font-stream PDF embedded font (sfnt) at offset 0xE460 5044 bytes