Malicious PDF — malware analysis report

Static analysis result for SHA-256 91f380a00eff57ee…

MALICIOUS

PDF

52.8 KB Created: 2020-07-20 03:35:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-07
MD5: 6712b7c25686291a65a5479b6f00ab84 SHA-1: 5e08b7fe52e4945ad83a1d09da909cb65b047a12 SHA-256: 91f380a00eff57ee6cf6b455cc7e2ae5f50d135ad9023bf1d4c8697dfda019f0
194 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded URLs, with heuristics indicating it is a link farm designed to redirect users. One critical heuristic specifically flags a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, appears to be a lure related to educational content. No scripts were extracted from this sample.

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.com/wb?keyword=solving%20quadratic%20equations%20with%20fractions%20worksheet In PDF document text
    • http://files.alexaharzan.com/uploads/1/3/0/7/130738871/8824849.pdfIn PDF document text
    • http://files.intellectualgroomers.com/uploads/1/3/1/3/131384171/4cb63d0c2dbbb12.pdfIn PDF document text
    • http://files.biancasams.com/uploads/1/3/1/1/131163872/makoretet-niwenof-libubakit.pdfIn PDF document text
    • http://files.hbluxury.co/uploads/1/3/1/4/131437576/4054971.pdfIn PDF document text
    • http://files.splatterpark.com/uploads/1/3/1/8/131856176/mulirapuwigarozomaze.pdfIn PDF document text
    • http://files.thmultisportcoaching.com/uploads/1/3/1/4/131438611/pijipemi.pdfIn PDF document text
    • http://files.thepitchthemovie.com/uploads/1/3/2/6/132695662/5783587.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://jetotijunedi.files.wordpress.com/2020/07/pukixevazalipizuxuxe.pdfIn PDF document text
    • https://letodatina.files.wordpress.com/2020/07/xilib.pdfIn PDF document text
    • https://xodavosubis.files.wordpress.com/2020/06/pakagiburamoziz.pdfIn PDF document text
    • https://defunudedi.files.wordpress.com/2020/06/52484121992.pdfIn PDF document text
    • https://zadedow817229965.files.wordpress.com/2020/07/59957804142.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/3753/7942/files/86636803066.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/1965/7628/files/jipirodetudusiledus.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tovaje.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/7432/1560/files/49976537165.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1560/2339/files/86215057869.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/0791/7729/files/84459171596.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/6906/3836/files/nuluwubepetibunukidopewa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/1674/1286/files/69149029633.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/6790/6977/files/45481315707.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/9825/1165/files/39727536331.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_off0000860b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x860B 5612 bytes
SHA-256: a60f6d76b51a53295203e21e7a57da6bee5c01dbda5389f9237d5b09b542e67f
font_01_sfnt_off0000991f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x991F 14236 bytes
SHA-256: f57c6d2a777ed26e0845eace38101e561a75b46ebaf849dd0a87324ab501991f