Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ffb2594eb6e7072…

MALICIOUS

PDF

46.0 KB Created: 2020-08-07 07:34:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2d945f4bc4548d78b5cf6ea4198e6475 SHA-1: 044e7934dad40ac108dbf3ef16fa4fb541b51ceb SHA-256: 3ffb2594eb6e70729b2a3b793550977317b8a5cfd4765aaec871de7d22390bd8
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, forming a link farm. One of these links, 'https://ttraff.ru/pify?keyword=bruchrechnung+%25C3%25BCbung+pdf', is identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body itself is heavily obfuscated and appears to be a lure for the malicious links.

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=bruchrechnung+%25C3%25BCbung+pdf
    • http://files.byzantineegypt.org/uploads/1/3/1/6/131636728/rodewed-tivuzi-mulusoxawuvi.pdf
    • http://files.favershamyouthcouncil.org/uploads/1/3/0/7/130739084/gelinozevune-goluki.pdf
    • http://files.cooper-lab.org/uploads/1/3/1/0/131070207/7720150.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jewepogepavab.pdf
    • https://cdn.shopify.com/s/files/1/0434/4931/9577/files/bombay_blood_group_download.pdf
    • https://cdn.shopify.com/s/files/1/0433/5907/6510/files/rulasegedosufem.pdf
    • https://cdn.shopify.com/s/files/1/0437/4790/1592/files/72604602975.pdf
    • https://cdn.shopify.com/s/files/1/0430/6301/7629/files/66270621725.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/71895612735.pdf
    • https://cdn.shopify.com/s/files/1/0427/8845/4559/files/6766791456.pdf
    • https://cdn.shopify.com/s/files/1/0432/2328/5928/files/susotuwetamixom.pdf
    • https://cdn.shopify.com/s/files/1/0433/8221/0725/files/mesonizigu.pdf
    • https://cdn.shopify.com/s/files/1/0433/6150/1336/files/postal_exam_473.pdf
    • https://cdn.shopify.com/s/files/1/0435/4244/6231/files/rugetisaravadixufirezab.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_off00005ded.bin
587e7517002de47c87c4debcabc106f3678ff492a0372903387d528171af1b1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DED 5304 bytes
font_01_sfnt_off00006fba.bin
72ecd48b2c207ad877338530757962faf511feb8c2e6c5c3925e26d203d096e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x6FBA 11132 bytes
font_02_sfnt_off0000947c.bin
f7f944af48a1f29a4fc81369acbb7667dc0c0bb312d09d0e658341ed730dbf86
pdf-font-stream PDF embedded font (sfnt) at offset 0x947C 16144 bytes