Malicious PDF — malware analysis report

Static analysis result for SHA-256 4906e5a95fee35da…

MALICIOUS

PDF

41.5 KB Created: 2020-08-30 01:08:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1382c869cae904c1cb51415f5f9bdb87 SHA-1: 85e604c12d13d1dc16f348dd01da8193b8bd01b1 SHA-256: 4906e5a95fee35daf6828adba50f32ae2011ad6e17c4c52129527a33533d689f
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with one prominent URL pointing to a known malicious redirector. The document body, though partially corrupted, includes text related to a free download lure for "Adobe indesign cc classroom in a book", suggesting a social engineering tactic to entice users to click the malicious link. The ML classifier 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.ru/wix?keyword=adobe+indesign+cc+classroom+in+a+book+free+download
    • https://static.usrfiles.com/ugd/3b0c81_60291ef39cc74b32bd77821370acd12b.pdf
    • https://static.usrfiles.com/ugd/b7ed05_fc74d4ba7a4945ba88d3bfb7fe4e85b0.pdf
    • https://static.usrfiles.com/ugd/b8c837_9d5d4559799d4e79b77e9104af2e55d2.pdf
    • https://cdn.shopify.com/s/files/1/0449/2935/1835/files/baixar_livros_gratis_em_portugues.pdf
    • https://cdn.shopify.com/s/files/1/0430/8946/1410/files/51215737659.pdf
    • https://cdn.shopify.com/s/files/1/0435/9972/4702/files/el_sintoismo.pdf
    • https://cdn.shopify.com/s/files/1/0428/2574/4547/files/43944335482.pdf
    • https://static.usrfiles.com/ugd/c7a620_e459a149701e434fb1c1f22ba0895ee8.pdf
    • https://static.usrfiles.com/ugd/b8c837_6183246d100d46d28dc6b95d7a1db236.pdf
    • https://cdn.shopify.com/s/files/1/0440/0896/4246/files/chamberlain_group_email_address_format.pdf
    • https://cdn.shopify.com/s/files/1/0432/4130/8320/files/truportal_access_control.pdf
    • https://cdn.shopify.com/s/files/1/0432/7371/5880/files/equilibrio_acido_base_sistema_respiratorio.pdf
    • https://cdn.shopify.com/s/files/1/0434/3706/4344/files/dojonijabenitisuzis.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_off00006345.bin
5ac78addf3a6587d7f7af5d4c0a67f7126ceeeacdcd13d1260a20d1c68cf3b10
pdf-font-stream PDF embedded font (sfnt) at offset 0x6345 5628 bytes
font_01_sfnt_off0000765d.bin
b604a420997359220bfa7f00dcc2fb6ae53d3413d8295f9cf9bb7f1aba2cda19
pdf-font-stream PDF embedded font (sfnt) at offset 0x765D 10288 bytes