Malicious PDF — malware analysis report

Static analysis result for SHA-256 491d33c0ea9b62c6…

MALICIOUS

PDF

40.9 KB Created: 2020-08-31 01:40:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c77c591880629f3b590bc6e7c1f13dca SHA-1: 5b30b2c6fb1163e14bec30ce40b4b3e4767edb55 SHA-256: 491d33c0ea9b62c64d99d53b3f6978070ca5d6cdde7880e77f1657d729330d3c
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 documents hosted on Shopify. One of these links, 'https://ttraff.com/wix?keyword=funcion+social+de+la+escuela', is identified as a malicious redirector. This suggests a link farm or SEO poisoning attack designed to lure users to malicious infrastructure. The ML classifier also strongly flagged this PDF as malicious.

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/wix?keyword=funcion+social+de+la+escuela
    • https://cdn.shopify
    • https://cdn.shopify.com/s/files/1/0434/8254/6341/files/durability_of_concrete_structures.pdf
    • https://cdn.shopify.com/s/files/1/0429/5750/4668/files/sisademawubitiwiwilawi.pdf
    • https://cdn.shopify.com/s/files/1/0433/2116/3941/files/bobcat_743_specs.pdf
    • https://static.usrfiles.com/ugd/a76634_d40225e5fd26426f815b6187e1251596.pdf
    • https://static.usrfiles.com/ugd/b8c837_8bcff15cfa1c4370b1d950ab64693aab.pdf
    • https://static.usrfiles.com/ugd/5be868_29fde5d048e64133bd701f3005a7c5cd.pdf
    • https://static.usrfiles.com/ugd/b8c837_4d067149c76c4836a66e93b2fd008265.pdf
    • https://static.usrfiles.com/ugd/b8c837_9b3437ac93af4eedb579bd23c38eb787.pdf
    • https://static.usrfiles.com/ugd/b8c837_304b6f131d7c41909e8048a29c1e6c37.pdf
    • https://static.usrfiles.com/ugd/4b68be_bafe83473c5d43078bf03565a8064ab0.pdf
    • https://cdn.shopify.com/s/files/1/0427/7121/8588/files/99720530059.pdf
    • https://cdn.shopify.com/s/files/1/0431/6836/6760/files/wofigarojobebev.pdf
    • https://cdn.shopify.com/s/files/1/0438/0701/5069/files/lejad.pdf
    • https://cdn.shopify.com/s/files/1/0431/8085/1364/files/tuximiz.pdf
    • https://cdn.shopify.com/s/files/1/0431/0879/4525/files/50097401613.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_off00006250.bin
f37b085e408ddccd23014f90cacbfe4a98b40d897234879ee901205289c1c0de
pdf-font-stream PDF embedded font (sfnt) at offset 0x6250 4792 bytes
font_01_sfnt_off000072a1.bin
28eb08cc630357f6bd2000b86ca7815a3db36e9a098b28a80503a3685931851d
pdf-font-stream PDF embedded font (sfnt) at offset 0x72A1 10724 bytes