Malicious PDF — malware analysis report

Static analysis result for SHA-256 6fb5d5e7683f3aa8…

MALICIOUS

PDF

41.4 KB Created: 2020-08-11 23:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 056013e8f988745674d4bea5504d7e8a SHA-1: 00f06e803f6ba3638984ad73282dfed82637a932 SHA-256: 6fb5d5e7683f3aa828fa0990c3ef36f8d9cd9bf075daa0e7572e2435aef4144a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to external PDF files, suggesting a link farm or SEO poisoning attempt. One critical heuristic identified a link to a known malicious redirector, `https://ttraff.cc/pify?keyword=candidiasis+vajinal+sintomas+pdf`, which is likely used to obscure the final malicious destination. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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/pify?keyword=candidiasis+vajinal+sintomas+pdf
    • http://files.blindinggray.com/uploads/1/3/1/4/131407138/f2c988d2.pdf
    • http://files.tamramccarthy.org/uploads/1/3/0/7/130776561/dudegaparixiz_lafix_makazomakigik_vowelabudupod.pdf
    • http://pazawuj.wangnaumannlab.com/uploads/1/3/1/3/131378776/b5213.pdf
    • http://nujewemur.section27alliance.com/uploads/1/3/1/4/131437423/c831b319652f61.pdf
    • http://files.pasadenaphysed.com/uploads/1/3/2/7/132711983/eabe073ad6.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0440/7810/4728/files/rufudi.pdf
    • https://cdn.shopify.com/s/files/1/0430/9801/3845/files/nabubevi.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jegatakufiritejat.pdf
    • https://cdn.shopify.com/s/files/1/0434/4807/4405/files/52028279357.pdf
    • https://cdn.shopify.com/s/files/1/0432/0467/3699/files/97238727154.pdf
    • https://cdn.shopify.com/s/files/1/0435/2029/5064/files/negozelepur.pdf
    • https://cdn.shopify.com/s/files/1/0431/8652/0228/files/matisyahu_one_day.pdf
    • https://cdn.shopify.com/s/files/1/0431/2930/7296/files/wilms_tumor_pathology.pdf
    • https://cdn.shopify.com/s/files/1/0435/6354/8833/files/16250258295.pdf
    • https://cdn.shopify.com/s/files/1/0435/4647/6708/files/veranepasavewivosobasodu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006440.bin
1c952cb3ffbc457ecd6b2442c14d70f186f74a942026cdbcddf34f77dd3daaad
pdf-font-stream PDF embedded font (sfnt) at offset 0x6440 5132 bytes
font_01_sfnt_off000075b4.bin
51ed6d2d92401b78a14504b8bc7ae5af9147096ae3a58a19be1ffab44029ae45
pdf-font-stream PDF embedded font (sfnt) at offset 0x75B4 10252 bytes