Malicious PDF — malware analysis report

Static analysis result for SHA-256 b310ab63be7611ea…

MALICIOUS

PDF

51.4 KB Created: 2020-07-13 01:03:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-10
MD5: f59288e17af7cfdf15f652c2e08fbe59 SHA-1: 4302e593f9aba44809f39f88c6d1c6c7ae139c0c SHA-256: b310ab63be7611ea3d5c65b678723eecac5757f4574c998b44e27934efdc2fc3
194 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with a critical heuristic firing for a PDF link farm. One of the primary links directs to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body appears to be obfuscated or corrupted, but the presence of 'memz clean download' and the link farm strongly suggest a malicious intent to redirect users to harmful 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.com/pify?keyword=memz+clean+download In PDF document text
    • http://files.glennfisherjewelry.com/uploads/1/3/1/4/131437147/dagivofiripil.pdfIn PDF document text
    • http://files.wilderblubordercollies.com/uploads/1/3/1/3/131398093/digisawomedefo.pdfIn PDF document text
    • http://files.bluemooncustombuilders.com/uploads/1/3/1/3/131398374/3bf47d026b4b9.pdfIn PDF document text
    • http://files.mindfulpolyglot.com/uploads/1/3/1/1/131164260/39dfb117.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/8957/6601/files/53619652911.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/7473/1685/files/91372269470.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/7643/5621/files/govudinixidesixokufipe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/5870/8118/files/50187048405.pdfIn PDF document text
    • https://jerorim.files.wordpress.com/2020/06/40295101573.pdfIn PDF document text
    • https://kixavokof.files.wordpress.com/2020/06/xuxuwujez.pdfIn PDF document text
    • https://pikerovin.files.wordpress.com/2020/06/zizazufiwefufumibawivido.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/texirid.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/0533/0083/files/gubusitiketonikip.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/6467/1909/files/bexezix.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/8996/1884/files/90742333387.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/9920/2467/files/sefujeroron.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/4684/6107/files/suzidometuwepowudab.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/1543/0553/files/xaniwirinev.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_off00008b07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8B07 4616 bytes
SHA-256: 8eeef7430f5391553d927b3f890a10bdcfc62d2fd6bb371dcb9df831f4c0fe1d
font_01_sfnt_off00009ab7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9AB7 11944 bytes
SHA-256: 91e5467d34ee354c469f7b8cfe19edf62c17157b510f9eab61edd29aa6e5833c