Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c79a5136da79915…

MALICIOUS

PDF

50.5 KB Created: 2020-08-20 07:33:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b5109a1d64732e80ff3ec5cb9d364cc2 SHA-1: fa91b39ec46801c8bd8e338413cdb529b78de102 SHA-256: 0c79a5136da79915a7283a164abd405d8e067e7909225c4864fad129fd548cd1
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text that appears to be a lure for a 'reference letter template academic'. The presence of many external PDF links suggests a link farm or SEO poisoning attempt, likely to obscure the malicious redirector.

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=reference+letter+template+academic
    • http://files.legaciesdiscovered.com/uploads/1/3/0/9/130969532/7862807.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0427/9320/5916/files/nozidop.pdf
    • https://cdn.shopify.com/s/files/1/0433/4593/6534/files/patebekomarabujurugaj.pdf
    • https://cdn.shopify.com/s/files/1/0428/7699/3702/files/deezloader_descargar_pc.pdf
    • https://cdn.shopify.com/s/files/1/0432/8990/3264/files/nexuzaputezolujadulim.pdf
    • https://cdn.shopify.com/s/files/1/0429/6704/0154/files/6110376361.pdf
    • https://cdn.shopify.com/s/files/1/0427/8986/3580/files/39345287516.pdf
    • https://cdn.shopify.com/s/files/1/0433/8991/1194/files/infinity_alt_code.pdf
    • https://cdn.shopify.com/s/files/1/0428/9055/9655/files/xafufetamasopofirafop.pdf
    • https://cdn.shopify.com/s/files/1/0438/2516/8544/files/pipojo.pdf
    • https://cdn.shopify.com/s/files/1/0433/3862/9270/files/76150588525.pdf
    • https://cdn.shopify.com/s/files/1/0430/4715/7911/files/gawesa.pdf
    • https://cdn.shopify.com/s/files/1/0431/5011/4965/files/zosyn_davis_drug_guide.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_off000089fd.bin
7809d625359e3deae0c7fea3423350cbbafe270451023bb88186e1dbc1ebaec5
pdf-font-stream PDF embedded font (sfnt) at offset 0x89FD 5132 bytes
font_01_sfnt_off00009b54.bin
b60dd134fa0f1a07d78ac33ff819c744e75c1a521f1ec90852bfdd9eac1f7f2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x9B54 9976 bytes