Malicious PDF — malware analysis report

Static analysis result for SHA-256 2660974b5e8648c5…

MALICIOUS

PDF

46.2 KB Created: 2020-07-19 21:33:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: eefa0e7d94a25541a248d2c26888c702 SHA-1: 2c39afd4aa235f46f132376f1c8ce820b2c90b66 SHA-256: 2660974b5e8648c506ae4e1794186f216466f2e3d48ffb70a22dbca66faf58c0
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1200 Hardware Add-in T1059.001 PowerShell

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool sometimes used to create malicious PDFs. The primary attack vector appears to be a phishing lure directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.cc/wb?keyword=metric%20conversion%20formulas%20pdf In PDF document text
    • http://files.hickmanhighschooltheatre.com/uploads/1/3/1/3/131379111/f61a0b993e1.pdfIn PDF document text
    • http://files.tampalandscapedesign.com/uploads/1/3/1/3/131379277/ganalosetetujujo.pdfIn PDF document text
    • http://files.aerialmediavisions.com/uploads/1/3/2/6/132695883/8434428.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://wegekivosum.files.wordpress.com/2020/07/48468495053.pdfIn PDF document text
    • https://bagofosuwawa.files.wordpress.com/2020/07/11662562611.pdfIn PDF document text
    • https://vorapizogu.files.wordpress.com/2020/07/35705725795.pdfIn PDF document text
    • https://rovekozo.files.wordpress.com/2020/07/5729604818.pdfIn PDF document text
    • https://xarefuwun.files.wordpress.com/2020/06/44498372356.pdfIn PDF document text
    • https://tepafazisera.files.wordpress.com/2020/07/xerajixuruwag.pdfIn PDF document text
    • https://xatemigifema20247951.files.wordpress.com/2020/07/dawaborutepukokadebefo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/4257/0401/files/xizulajavigogujopasida.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/7754/1787/files/nizixajasiwowetabeput.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/7055/3250/files/radalejozaxinoseluvo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/fiwowosilikaragufes.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/dosoxuwananeworatimuk.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/1556/1638/files/rezejuxexugiko.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/9436/7649/files/guxufifewaxodukubirebeb.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000077a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x77A9 5248 bytes
SHA-256: 368f05f205c1801ae35271593a9847c3094e1c985a860f76e570c0e85dad78f4
font_01_sfnt_off00008973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8973 10060 bytes
SHA-256: 6c4f57d73dffb7727e7f51d4e72f66573ce290736b79412ef1b6f760bc5ea586