Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3899d51267bcf37…

MALICIOUS

PDF

66.7 KB Created: 2021-04-14 02:22:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 01f5b912c5cda23065210fed09768f0c SHA-1: db9ccd234c487d22cad54e509bcb65a4e105161b SHA-256: d3899d51267bcf37c4ecdfa9a43532b200b68b87c4854433fafe4f3f947ece1e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The document body, though heavily obfuscated, contains references to 'Dirty sprite 2 free download', suggesting a lure for users to obtain potentially unwanted or harmful software. The presence of numerous embedded 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-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 http://klm3fg.grhosting.cz/sites/default/files/webform/files/56601188302.pdf In PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/tizagoge.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/53478461308.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/38780162719.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/1232685222.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/28941778760.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/kimakevenowafuxopepasu.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/fukixuliwidopisoduzurapi.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/96043924660.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/16921441106.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/jokefogebefuzifuzew.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/47147916176.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/3242210986.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/bogobovimefegaf.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/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=dirty+sprite+2+free+downloadPDF link annotation
    • https://www.healthdata.org/sites/default/files/resumes/mevupuxapiledowitire.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_off0000c639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC639 5360 bytes
SHA-256: 06958c834aa6546af955ed7850d2b09b5dfcb102d76d422fc00068a9d00dd55e
font_01_sfnt_off0000d8a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A6 10884 bytes
SHA-256: e63712e7ec3a020702cf303677d911248d427e535a7e9faeb1d3a37f4f9477bb