Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b8396a18611a515…

MALICIOUS

PDF

35.2 KB Created: 2020-09-01 00:10:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb7feb222e95ebc4d3de321075b917e4 SHA-1: ac5f8966231a402a483df9390f4ea9edf449a46e SHA-256: 9b8396a18611a515940cf6e83086f116ef00addbf62043c0e374d67fd2f2b1b5
154 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many of which point to a redirector service. The document body, though heavily obfuscated, appears to be a lure related to educational materials. The primary malicious IOC is the redirector URL, which is likely used to funnel victims to further malicious content. The ML classifier strongly supports the malicious nature of this PDF.

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.ru/pify?keyword=phet+molecular+shapes+simulation+worksheet+answers+pdf
    • https://static.usrfiles.com/ugd/362633_522d1e0571624edbae7f393ac86ab6a4.pdf
    • https://static.usrfiles.com/ugd/b8c837_f25d75747fc24f3a9c1c7357fc2bf807.pdf
    • https://static.usrfiles.com/ugd/857e61_49c132e533c94be1afa1f99d5179494c.pdf
    • https://static.usrfiles.com/ugd/de3d83_c61265f90e0249389d981f8072dd0fd4.pdf
    • https://static.usrfiles.com/ugd/ea78e0_76575bd45da94af9ba650a2b3199f83f.pdf
    • https://cdn.shopify.com/s/files/1/0432/6726/0576/files/calculus_jon_rogawski.pdf
    • https://cdn.shopify.com/s/files/1/0435/6990/5825/files/73726039897.pdf
    • https://cdn.shopify.com/s/files/1/0439/1724/6632/files/lumebogamaxibomaselobe.pdf
    • https://cdn.shopify.com/s/files/1/0429/2752/1948/files/62224286951.pdf
    • https://cdn.shopify.com/s/files/1/0452/5198/5565/files/vulijibovitipemigesi.pdf
    • https://cdn.shopify.com/s/files/1/0458/3289/6675/files/vcds_16._8_crack.pdf
    • https://cdn.shopify.com/s/files/1/0437/1644/4311/files/nolavowutoxodemiluvipu.pdf
    • https://cdn.shopify.com/s/files/1/0437/3551/5290/files/runabogizopado.pdf
    • https://cdn.shopify.com/s/files/1/0433/9492/4694/files/cattle_production_and_management.pdf
    • https://cdn.shopify.com/s/files/1/0428/0962/2691/files/26421979758.pdf
    • https://cdn.shopify.com/s/files/1/0433/2955/2552/files/vezipeluvexotu.pdf
    • https://cdn.shopify.com/s/files/1/0436/8711/6965/files/nogela.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_off0000497d.bin
de66c0e408fbb98a46925bed3245485443b0721b86b04b922339c7a6cadb6ec3
pdf-font-stream PDF embedded font (sfnt) at offset 0x497D 5552 bytes
font_01_sfnt_off00005c40.bin
03b352650d57af6bc816de3a14c92fcda4330a4cded59b4f411c2bd326954746
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C40 10252 bytes