Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1e8ed689710f00b…

MALICIOUS

PDF

36.7 KB Created: 2020-08-17 10:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d49ba5fda853f08d0865cbdfcb75654e SHA-1: 3ccdec5585185e52632473e752e592cc3cf4192e SHA-256: a1e8ed689710f00b5ffb2842c7e4c8e775c06f09cf62e074a59154dff8e631b3
152 Risk Score

Malware Insights

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

The PDF contains a link that redirects to known malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains the same URL and appears to be a lure for a worksheet. The PDF_SEO_LINK_FARM heuristic suggests a large number of similar links were generated, likely for SEO poisoning or link farming. The ML classifier strongly indicates 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=dangling+and+misplaced+modifiers+worksheet+pdf
    • http://files.poeticexpressionsforyou.com/uploads/1/3/0/8/130873708/5864917.pdf
    • https://cdn.shopify.com/s/files/1/0432/2502/2621/files/44742122775.pdf
    • https://cdn.shopify.com/s/files/1/0432/7243/7910/files/fuxajawo.pdf
    • https://cdn.shopify.com/s/files/1/0438/4319/0946/files/accounting_information_systems_11th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0431/1403/7409/files/rajak.pdf
    • https://cdn.shopify.com/s/files/1/0430/4168/5665/files/kelojikivivaxunizavererig.pdf
    • https://cdn.shopify.com/s/files/1/0437/8293/0593/files/fagavekemorinazigozudi.pdf
    • https://cdn.shopify.com/s/files/1/0438/5187/4466/files/megafitazedikumadopepap.pdf
    • https://cdn.shopify.com/s/files/1/0433/3453/3275/files/acetaminophen_tylenol_davis.pdf
    • https://cdn.shopify.com/s/files/1/0430/5738/1530/files/understanding_business_ethics_stanwick.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kubogofire.pdf
    • https://cdn.shopify.com/s/files/1/0433/4610/0377/files/fadokemevadex.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/luzugojozawok.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_off00005357.bin
f46f81c340769888a885100323a00b236285807630c1a25c599f85daba9ed113
pdf-font-stream PDF embedded font (sfnt) at offset 0x5357 5724 bytes
font_01_sfnt_off000066b8.bin
18b4d059d652afc09c126fc331a4f4c6cd4e9db770fed63c75cf7d5fb0d64578
pdf-font-stream PDF embedded font (sfnt) at offset 0x66B8 9052 bytes