Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87ac67b21bfdc08…

MALICIOUS

PDF

51.6 KB Created: 2020-07-10 08:31:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 6dda2c5277c67c6740a4c25b0c25ee44 SHA-1: ffa2e8ee6133062005b2ecd57609cfa8da6ac932 SHA-256: b87ac67b21bfdc08256598b873ce3ad90de9e086a90fe786ae8145dd38746afb
184 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded links, many of which point to external PDF files hosted on various domains. One prominent link redirects to 'https://ttraff.cc/wb?keyword=sintomas%20de%20tuberculosis%20pulmonar%20pdf', suggesting a lure to disguise malicious activity. The document body, though partially obfuscated, contains keywords related to tuberculosis and the PDF's creation tool, reinforcing the lure. The presence of numerous external links indicates a link farm or redirection strategy, likely to distribute further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • 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://ttraff.cc/wb?keyword=sintomas%20de%20tuberculosis%20pulmonar%20pdf In PDF document text
    • http://files.monroesportsmansclub.com/uploads/1/3/2/7/132740549/dupipekokalixunag.pdfIn PDF document text
    • http://files.laredounited.org/uploads/1/3/0/9/130969532/jowet.pdfIn PDF document text
    • http://files.misshortonsclass.com/uploads/1/3/1/8/131871494/5598380.pdfIn PDF document text
    • http://files.diylabourpain.co.uk/uploads/1/3/1/8/131856877/467c3d96.pdfIn PDF document text
    • http://files.youthadvocatespdx.org/uploads/1/3/1/3/131398182/rijavojadavopizav.pdfIn PDF document text
    • http://files.cranbrookdistrictteachersassociation.com/uploads/1/3/1/8/131871494/8c401b.pdfIn PDF document text
    • http://files.madala134.com/uploads/1/3/1/4/131453056/8496004.pdfIn PDF document text
    • http://files.vk3sn.net/uploads/1/3/1/8/131871894/d40f274a4b81b4.pdfIn PDF document text
    • http://files.danielpsgoh.com/uploads/1/3/0/8/130873758/7861376.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://fupukofove.files.wordpress.com/2020/06/kopakuwafatelavogiwetikaw.pdfIn PDF document text
    • https://vimagifa577894512.files.wordpress.com/2020/06/lovofurewataxazu.pdfIn PDF document text
    • https://vusuletameta.files.wordpress.com/2020/07/tunuximetemapuvabufog.pdfIn PDF document text
    • https://jitunaf.files.wordpress.com/2020/06/79168191082.pdfIn PDF document text
    • https://xawuzebufo.files.wordpress.com/2020/06/26433020718.pdfIn PDF document text
    • https://wepupip.files.wordpress.com/2020/07/vuxuroxajuxadagafelelili.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/38608120386.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/38970143778.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/66541571973.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/ralaguguzovepusumizus.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/womosoravitixugefiwil.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/83406059157.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_off0000887f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x887F 5424 bytes
SHA-256: 148d3688c19443184c30a61e1a6c46175d3f27a485ec3d24e30f6c657e22bf42
font_01_sfnt_off00009ab6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9AB6 11392 bytes
SHA-256: bd98c487157078622c4a58e140178c847b399685b0e96967998aeef16b42a3aa