Malicious PDF — malware analysis report

Static analysis result for SHA-256 38fc492b9e91566a…

MALICIOUS

PDF

42.1 KB Created: 2020-09-01 08:30:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d5e03a1577cfecdb0383ff98e6db0c5a SHA-1: a94db9df7084c8411cc2149fa8a3cc6222607fc5 SHA-256: 38fc492b9e91566ac7925632bb5c2a05659259ee8fefe7bd62ab3341700096c2
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, with one identified as a known malicious redirector. The document body, though garbled, contains text related to educational worksheets and references the redirector URL. This suggests a lure to a malicious site disguised as educational content. No scripts were extracted from this sample.

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/wix?keyword=multiplication+of+integers+worksheet+for+grade+7
    • https://static.usrfiles.com/ugd/73f3b0_0a4a8b4816254634b6bdbaa37a4cd9ee.pdf
    • https://static.usrfiles.com/ugd/fd30ac_3b219b97955a478ab38273156ade8fff.pdf
    • https://static.usrfiles.com/ugd/a44510_a92b49fe35c141a0a25579700f48ad1d.pdf
    • https://static.usrfiles.com/ugd/edb4a7_a5776ac232824407b5c5b299627b317d.pdf
    • https://static.usrfiles.com/ugd/b65acf_04a40a6c09074949ac8eed9077102958.pdf
    • https://static.usrfiles.com/ugd/b8c837_27a1d5dae6d6492e9c161aa61f94b069.pdf
    • https://static.usrfiles.com/ugd/7f16bd_c8507326d8ae46feb8b75beb1a70ae7f.pdf
    • https://static.usrfiles.com/ugd/3649d2_d0e26d8da1c14a8bae57b1fb6a7cf8e3.pdf
    • https://cdn.shopify.com/s/files/1/0434/1281/6026/files/caboclo_guerreiro.pdf
    • https://cdn.shopify.com/s/files/1/0435/4598/5192/files/kafodukibosowekudu.pdf
    • https://cdn.shopify.com/s/files/1/0428/1306/3327/files/nesojegawetar.pdf
    • https://cdn.shopify.com/s/files/1/0432/6971/8172/files/3607432882.pdf
    • https://cdn.shopify.com/s/files/1/0434/5180/9957/files/assembly_language_programming_arm_cortex_m3_vincent_mahout.pdf
    • https://cdn.shopify.com/s/files/1/0431/5476/8021/files/93582744217.pdf
    • https://cdn.shopify.com/s/files/1/0433/3027/3434/files/bleacher_report_champions_league_broadcast.pdf
    • https://cdn.shopify.com/s/files/1/0428/3016/8230/files/cara_membuat_blog_pribadi_di_hp_android.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_off00006449.bin
6b6251d209bc2c9017fcbaa9dc502ea019c7487cfb4a38d76372976e65616f5b
pdf-font-stream PDF embedded font (sfnt) at offset 0x6449 5656 bytes
font_01_sfnt_off000077a9.bin
da9a9a6f52331443ec6b215f212c2e1efabdbcda2a24c7762d7e49a33c4f0778
pdf-font-stream PDF embedded font (sfnt) at offset 0x77A9 10584 bytes