Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5ee7ade85d10de8…

MALICIOUS

PDF

44.6 KB Created: 2020-08-09 23:36:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f36889a157121f91add477c0a6e6d8d7 SHA-1: 73f374172fbe0afb35ea24b6263b513466883e6c SHA-256: a5ee7ade85d10de8f4121deef295e5b762e944b6d79b4b09b9b911b292972cf2
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many of which point to external PDF files hosted on various domains, including a known malicious redirector. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains text related to 'musical appreciation pdf' and the authoring application 'wkhtmltopdf', suggesting a lure to disguise the malicious link farm.

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.ru/pify?keyword=definition+of+musical+appreciation+pdf
    • http://kutix.kununurramarkets.com/uploads/1/3/0/8/130814411/xuxibogagelixupu.pdf
    • http://miled.rongoodine.com/uploads/1/3/1/0/131070356/mamumu.pdf
    • http://muxufiju.kazquilting.com/uploads/1/3/2/7/132712615/fezulusedilaza_gemugenejezum_giweke.pdf
    • http://files.thinkdelirium.com/uploads/1/3/1/3/131380063/2236677.pdf
    • http://files.workingmolossersunited.com/uploads/1/3/1/1/131164440/gibadenapijedux.pdf
    • https://cdn.shopify.com/s/files/1/0438/6773/4171/files/disud.pdf
    • https://cdn.shopify.com/s/files/1/0439/4670/5051/files/energy_storage_market.pdf
    • https://cdn.shopify.com/s/files/1/0435/1095/6196/files/vyasa_yoga_bhashya.pdf
    • https://cdn.shopify.com/s/files/1/0432/8220/2782/files/nizufegokamezu.pdf
    • https://cdn.shopify.com/s/files/1/0430/1121/1425/files/85804634464.pdf
    • https://cdn.shopify.com/s/files/1/0430/6305/0394/files/oxford_dictionary_online.pdf
    • https://cdn.shopify.com/s/files/1/0430/7910/6724/files/biografia_fernandinho_beira_mar.pdf
    • https://cdn.shopify.com/s/files/1/0445/3964/2015/files/forming_storming_norming_performing_deutsch.pdf
    • https://cdn.shopify.com/s/files/1/0432/3485/3021/files/21427500863.pdf
    • https://cdn.shopify.com/s/files/1/0433/0982/6213/files/babopegoxalavukaxometu.pdf
    • https://cdn.shopify.com/s/files/1/0432/5064/7204/files/liliwimu.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006f19.bin
80c478497c5c0d594751b389fece35f7128f03d382af0e497f25a99a43172751
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F19 5300 bytes
font_01_sfnt_off00008111.bin
6fb275ee688181bbc621130d45b98a85d416d2738d52bacbb323e951afaad4cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x8111 10616 bytes