Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f70fdbb3b28f719…

MALICIOUS

PDF

78.5 KB Created: 2021-04-25 09:12:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 9f981b4f550aa17974409f350fd7c26f SHA-1: a4ba29edc81e7464a58bc45ef704626afbf879bc SHA-256: 5f70fdbb3b28f7192927df9ac8d3dc2ebf303ac129919388284e0e766da401a4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.afscme65.org/system/files/webform/11173368180.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/52499587618.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/9555400870.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/1232685222.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/25507329945.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/nolukaronedibikix.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/6659556688.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=2009+dodge+caravan+sxt+featuresPDF link annotation
    • https://umatter.princeton.edu/system/files/webform/requests/roporopapoviz.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/tuvoluxasivawujunaz.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/wosevojowavinojefe.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/21338807989.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/26098210740.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/83605599331.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/16616798570.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
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD504 5452 bytes
SHA-256: d20eea04e4eeaf8c1d58b1cba941592fe8941e52062d91efa1d462b826b0bfe3
font_01_sfnt_off0000e786.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE786 6068 bytes
SHA-256: 7a02da73c5ff24218d04b188db7d31ceb9303d5dedd43b645f18a615a19d9b6a
font_02_sfnt_off0000f737.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF737 11064 bytes
SHA-256: 788eceead7f8ab84c105dba5dce4b3e9811f2c06310c06bc85dffa2e3e79815e
font_03_sfnt_off00011d31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D31 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f