Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6d1dcca87109d38…

MALICIOUS

PDF

42.6 KB Created: 2020-08-15 12:40:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e24d95cb783f55c332bcea920c82446e SHA-1: 90277cf3ed9e5fbe3f9e6fdcf1ef85a6200fa802 SHA-256: a6d1dcca87109d385f474ca0743986a1aed56f849ee29fa4c849c91be67e4830
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a malicious redirector link disguised as a crossword puzzle clue, aiming to trick users into clicking it. The ML classifier strongly indicated maliciousness, and the presence of numerous external PDF links, many hosted on potentially compromised or malicious domains, further supports this. The document body itself is heavily obfuscated, but the presence of the malicious URL is clear.

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=the+cell+crossword+puzzle+clues+answers
    • http://files.norwegian-food.com/uploads/1/3/2/6/132681670/2c38ebc826f9d4.pdf
    • http://files.gesikpt.com/uploads/1/3/1/3/131379503/pizadaxasaxo.pdf
    • http://nizilab.familymatterseducation.com/uploads/1/3/1/4/131453284/8ae35888.pdf
    • http://files.clubsaustralia-industrial.com/uploads/1/3/1/0/131070501/3356479.pdf
    • http://fimoro.pahasapagrotto.org/uploads/1/3/0/8/130874365/lemowosozexirapalala.pdf
    • https://cdn.shopify.com/s/files/1/0435/5627/4339/files/writer_s_reference_7th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0431/4211/9592/files/16258501467.pdf
    • https://cdn.shopify.com/s/files/1/0429/8542/2997/files/24407377519.pdf
    • https://cdn.shopify.com/s/files/1/0433/2208/1448/files/zorobapuxe.pdf
    • https://cdn.shopify.com/s/files/1/0427/6636/8935/files/30805866492.pdf
    • https://cdn.shopify.com/s/files/1/0430/6527/8625/files/55096763524.pdf
    • https://cdn.shopify.com/s/files/1/0439/8442/1022/files/mezosotolufabototuv.pdf
    • https://cdn.shopify.com/s/files/1/0430/3847/4397/files/jenalibezubi.pdf
    • https://cdn.shopify.com/s/files/1/0434/2526/7877/files/warlock_leveling_guide.pdf
    • https://cdn.shopify.com/s/files/1/0440/5143/1574/files/the_axiom_of_choice_thomas_jech.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_off000068bb.bin
fc5684975adc506ff34b40f46342def7045c38bc43240ceda53c9c46b9f1d29c
pdf-font-stream PDF embedded font (sfnt) at offset 0x68BB 5252 bytes
font_01_sfnt_off00007aa1.bin
9905cad9149c977a732c471afe414a6ba76bead69dc34722b6f19dd6711cb771
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AA1 10120 bytes