Malicious PDF — malware analysis report

Static analysis result for SHA-256 77cd919db1c5501f…

MALICIOUS

PDF

42.5 KB Created: 2020-11-03 02:35:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 63794a537521bba2dcb564fc88dae7b5 SHA-1: ec96f67910aa8d3f50c382f914d7cacecbe79863 SHA-256: 77cd919db1c5501fbe494f8b5da67a7140992784c1efcc0fcd1efbeb1fc25104
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links, many pointing to benign-looking PDFs hosted on Shopify and S3, but one critical link directs to a known malicious redirector. This suggests an attempt to lure users to malicious infrastructure, possibly for further exploitation or phishing. The ML classifier strongly supports the malicious verdict.

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://cctraff.ru/aws?keyword=culture+club+i+m+afraid+of+me
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0495/4793/5896/files/maxwell_house_instant_coffee_decaf.pdf
    • https://uploads.strikinglycdn.com/files/8ffcd912-b196-49a8-ad82-584fa0c1b4e2/wazivefujokun.pdf
    • https://cdn.shopify.com/s/files/1/0436/2049/9620/files/bugatememavatonakunijoz.pdf
    • https://cdn.shopify.com/s/files/1/0500/6504/7743/files/womodu.pdf
    • https://s3.amazonaws.com/jukezeluf/komigoxutolajivoridowubuk.pdf
    • https://s3.amazonaws.com/gajabedafot/daforerajalizagavip.pdf
    • https://cdn.shopify.com/s/files/1/0266/9530/3365/files/xiradidanoxevumepokaloti.pdf
    • https://s3.amazonaws.com/damerirazib/kanimevinuduvexodalizi.pdf
    • https://cdn.shopify.com/s/files/1/0506/9445/5450/files/xojojuwojedapajanunesopub.pdf
    • https://cdn.shopify.com/s/files/1/0496/2212/2660/files/extraordinary_ones_moba_guide.pdf
    • https://s3.amazonaws.com/salade/duracell_nimh_battery_charger_cef14uk4_instructions.pdf
    • https://cdn.shopify.com/s/files/1/0500/7484/5375/files/27505279949.pdf
    • https://s3.amazonaws.com/ditiruz/bojexumiporuduxanusafodar.pdf
    • https://s3.amazonaws.com/levovod/gezuzilobugifu.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_off00006962.bin
052226c4da84a48a0bc33deb21ab7344d7de0452522b4c512ec174a5c8441759
pdf-font-stream PDF embedded font (sfnt) at offset 0x6962 5032 bytes
font_01_sfnt_off00007a62.bin
a2750fe9528bf3c1dd7a0f490265b24c6b4c2e449a59104d2689312ad37da7c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A62 10272 bytes