Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b5c3e6cd23cdd54…

MALICIOUS

PDF

45.2 KB Created: 2020-08-17 05:17:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 190dc2265ef4aa86ddcb9a6aa5712727 SHA-1: f1ba1b5aa9f923ddf0708012f84895d0a95eb51b SHA-256: 2b5c3e6cd23cdd54621a6eeefbaef284c4a48cfb838911adc5a8982a2e1efd6a
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to a link farm hosted on Shopify. One of the primary links, however, redirects to 'ttraff.cc', a known malicious redirector. The document body, though heavily obfuscated, contains the text 'Medical dictionary oxford free' and the malicious URL, suggesting a lure to trick users into clicking the malicious link. The ML classifier also strongly indicated maliciousness.

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/pify?keyword=medical+dictionary+oxford+free
    • http://files.hkcofc.com/uploads/1/3/2/6/132683111/lobojevaresale_jojolurirukekof_nunaduwarutare_rulilik.pdf
    • http://lopufosix.donateoakland.org/uploads/1/3/1/1/131164250/lipunir_dufumavuzagaxo_bolededopaze_zedunajakogite.pdf
    • https://cdn.shopify.com/s/files/1/0432/6037/9286/files/42436048926.pdf
    • https://cdn.shopify.com/s/files/1/0428/5209/0022/files/before_we_get_married_novel_ayamei.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xugifewelogukepebokiz.pdf
    • https://cdn.shopify.com/s/files/1/0434/0210/0899/files/82668825371.pdf
    • https://cdn.shopify.com/s/files/1/0435/9074/6271/files/classes_of_antidiabetic_drugs.pdf
    • https://cdn.shopify.com/s/files/1/0429/8987/9445/files/92650257802.pdf
    • https://cdn.shopify.com/s/files/1/0431/8684/7903/files/anestesia_epidural_baja_en_bovinos.pdf
    • https://cdn.shopify.com/s/files/1/0428/5657/9228/files/91361821101.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005c21.bin
0e8ffa07e7f42dc7e4f35205d791bc4d931e91d67a180ea8e91f933066e37740
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C21 5012 bytes
font_01_sfnt_off00006d48.bin
af6646f16a0b2f4226c11dfbe5c922f5eac872c48ca7864049670dbec42dcbff
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D48 10624 bytes
font_02_sfnt_off000091c4.bin
4354bd37e85197a997b2f6c8c8698034d2711068b41d1b66819094364c364bcc
pdf-font-stream PDF embedded font (sfnt) at offset 0x91C4 16544 bytes