Malicious PDF — malware analysis report

Static analysis result for SHA-256 27b140b7e0d6fdaf…

MALICIOUS

PDF

43.8 KB Created: 2020-08-20 10:39:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: efb4ec43ecf955fe02739d5ed621b003 SHA-1: cdfeeb3c0a3915af291f799fe59ab4bbc804b2aa SHA-256: 27b140b7e0d6fdafcfb72fd2656449ecbbfcd9cf40d47d8a706dd3c1a07479c6
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, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL for the malicious redirector and several other URLs hosted on Shopify, suggesting a link farm or redirection scheme. 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.com/pify?keyword=chambal+kannada+movie+songs
    • http://files.sandraharveyphotography.com/uploads/1/3/2/7/132740836/5e39f1743c06d7.pdf
    • http://files.eghsfinearts.com/uploads/1/3/2/6/132682585/jevagiwi.pdf
    • https://cdn.shopify.com/s/files/1/0434/6078/8390/files/33386915329.pdf
    • https://cdn.shopify.com/s/files/1/0429/3489/4755/files/vebaxivimob.pdf
    • https://cdn.shopify.com/s/files/1/0431/3173/2122/files/1484302633.pdf
    • https://cdn.shopify.com/s/files/1/0432/7335/5424/files/30518279272.pdf
    • https://cdn.shopify.com/s/files/1/0440/2656/0677/files/free_cello_sheet_music_pirates_caribbean.pdf
    • https://cdn.shopify.com/s/files/1/0434/4751/7341/files/gogedudatetok.pdf
    • https://cdn.shopify.com/s/files/1/0427/9074/8316/files/2020_cadillac_sts_manual.pdf
    • https://cdn.shopify.com/s/files/1/0433/0654/9406/files/93513769597.pdf
    • https://cdn.shopify.com/s/files/1/0432/7053/7374/files/antidoto_benzodiacepinas.pdf
    • https://cdn.shopify.com/s/files/1/0429/2263/9527/files/45992385716.pdf
    • https://cdn.shopify.com/s/files/1/0437/7565/6094/files/90825072315.pdf
    • https://cdn.shopify.com/s/files/1/0437/3698/9850/files/21513243917.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_off0000663f.bin
bca126767e101ace2c224526255c438cd765d431ef5dfb866bcdbf265dc1d2a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x663F 5312 bytes
font_01_sfnt_off00007836.bin
8864ca323840dab8f7996ab18cff7ddf0649638d377f2b56b6188398d77e24b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7836 13156 bytes