Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f5e100fc4174b66…

MALICIOUS

PDF

39.3 KB Created: 2020-08-30 18:12:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b02f66dfa215c3606dd0b1661d303643 SHA-1: d5aa672e12238a2a96b80804ae472c7dae226ab9 SHA-256: 6f5e100fc4174b66e245234da7d0ec9505ea12fd08e5f8036b78239b0a2d6bd4
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of embedded links, with one identified as a malicious redirector. The document body, though obfuscated, contains text related to a worksheet and the authoring application 'wkhtmltopdf', suggesting a lure to trick users into clicking the malicious links. The presence of numerous PDF links points towards a link farm strategy to distribute malicious content.

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.cc/wix?keyword=worksheet+11.+6+subjunctive+mood
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0430/4466/7553/files/angna_padharo_maharani_dj_vicky_song.pdf
    • https://cdn.shopify.com/s/files/1/0432/4245/5207/files/katalog_exhaust_fan_panasonic.pdf
    • https://cdn.shopify.com/s/files/1/0429/2041/1303/files/vuwiborasobajebowiba.pdf
    • https://cdn.shopify.com/s/files/1/0429/4190/7110/files/febapelek.pdf
    • https://static.usrfiles.com/ugd/0047a4_fd7f043b72fa4c41a007252296ce0a13.pdf
    • https://static.usrfiles.com/ugd/0fdb6d_65ed03f735ae4fefaabe62aa76f04e32.pdf
    • https://static.usrfiles.com/ugd/cac9e4_356c093655b14760a5347a3366739f41.pdf
    • https://static.usrfiles.com/ugd/97368a_23f30db519094205a32bddd2fa4f506a.pdf
    • https://static.usrfiles.com/ugd/9ec29b_ea448a04a3fa4adf85e860aaf6cfa71d.pdf
    • https://static.usrfiles.com/ugd/6cf392_d9351949245a489ba5d5292fbab6ed9d.pdf
    • https://static.usrfiles.com/ugd/dd4472_819986288d794405a283b62d2fa4aa23.pdf
    • https://cdn.shopify.com/s/files/1/0432/9180/3801/files/22523408910.pdf
    • https://cdn.shopify.com/s/files/1/0431/3609/0274/files/3953510064.pdf
    • https://cdn.shopify.com/s/files/1/0428/3600/0931/files/33830369709.pdf
    • https://cdn.shopify.com/s/files/1/0427/6033/9623/files/exercise_to_be_present_simple.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_off00005b03.bin
302925a104ec0e6560648723b9a7483dc63cdf2eb995f0853652962ed0826298
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B03 5528 bytes
font_01_sfnt_off00006dce.bin
b9543fe3a20203d12779f73d7bf6c15bc3cc89830a990a4e381cc2293f2b2f27
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DCE 10188 bytes