Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4f328b4d34b53b7…

MALICIOUS

PDF

43.8 KB Created: 2020-08-28 01:32:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a486e5950a34416d03b7f433da6ced2 SHA-1: 821bafd98b67eb8c823b51f91ffe312d90a74b8a SHA-256: a4f328b4d34b53b72b8827e2ba1a8b4bcbe864310096aeb18eed0fb88cd2eab1
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector at ttraff.ru. This suggests a link farm or SEO poisoning tactic designed to redirect users to malicious content. 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://ttraff.ru/pify?keyword=distribucion+normal+ejercicios+resueltos+paso+a+paso
    • http://tozofexof.drowningpreventionresources.org/uploads/1/3/1/3/131383483/3ea7eba99ee7.pdf
    • https://cdn.shopify.com/s/files/1/0435/7187/1912/files/84085884263.pdf
    • https://cdn.shopify.com/s/files/1/0429/6710/5687/files/buku_agama_islam_kelas_12_sma_kurikulum_2020.pdf
    • https://cdn.shopify.com/s/files/1/0432/9937/3214/files/american_english_file_free.pdf
    • https://cdn.shopify.com/s/files/1/0431/2930/7293/files/judal.pdf
    • https://cdn.shopify.com/s/files/1/0446/3358/7875/files/sheet_music_greensleeves.pdf
    • https://cdn.shopify.com/s/files/1/0434/1753/4629/files/46734633533.pdf
    • https://cdn.shopify.com/s/files/1/0452/6155/3826/files/begum_hazrat_mahal_online_form_2019.pdf
    • https://cdn.shopify.com/s/files/1/0431/2150/8506/files/angular_interview_questions.pdf
    • https://cdn.shopify.com/s/files/1/0441/4459/1000/files/controle_da_administrao_pblica_estratgia_concursos.pdf
    • https://cdn.shopify.com/s/files/1/0433/3282/9342/files/83997825341.pdf
    • https://cdn.shopify.com/s/files/1/0430/8339/9329/files/all_casino_games.pdf
    • https://cdn.shopify.com/s/files/1/0434/0239/5798/files/23187710241.pdf
    • https://cdn.shopify.com/s/files/1/0433/0346/9221/files/shake_hands_with_the_devil_book.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_off00006926.bin
efc92bbdaccc5a610c4c4f7541df2317145a9d0cd2147e3e9358e0d8b9797ce8
pdf-font-stream PDF embedded font (sfnt) at offset 0x6926 5292 bytes
font_01_sfnt_off00007b0a.bin
b0185a850d71c0288d7ef2b49d37394f0202d8afb92e6919c09596c7003017c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B0A 11888 bytes