Malicious PDF — malware analysis report

Static analysis result for SHA-256 b53dbb2b7f4c158e…

MALICIOUS

PDF

44.4 KB Created: 2020-08-20 04:32:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d2a269424c1b5a8cf3279d32281148a4 SHA-1: b0d3e881977703f8308878734c07e760b147734b SHA-256: b53dbb2b7f4c158e6c6856af77f26fd2bff675706caa3d385d7991608e7cc4a9
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one specifically identified as a malicious redirector. The document body text, though partially garbled, includes 'Mlsu portal admission form' and a URL that points to a redirector. This suggests a phishing or scam attempt where users are tricked into clicking the link, which then leads to malicious content. The ML classifier strongly supports the malicious nature of this PDF.

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=mlsu+portal+admission+form
    • http://tadewig.marygreenmanor.co.uk/uploads/1/3/0/7/130775436/316370.pdf
    • http://dawuxejop.tavisdupreez.com/uploads/1/3/1/4/131438304/migakiwutekufalawez.pdf
    • http://sarab.pontoonbaptistchurch.org/uploads/1/3/1/4/131482995/gexunagis_nenepu_mopolajos_warituruxejev.pdf
    • https://cdn.shopify.com/s/files/1/0427/4615/1078/files/mugapagukedog.pdf
    • https://cdn.shopify.com/s/files/1/0433/5622/5686/files/busunolevomimatadoxate.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/rafudegilezenetizaxesuvos.pdf
    • https://cdn.shopify.com/s/files/1/0428/2168/1315/files/jorajelolatasuzil.pdf
    • https://cdn.shopify.com/s/files/1/0435/7960/5147/files/acto_administrativo_colombia.pdf
    • https://cdn.shopify.com/s/files/1/0430/0213/4681/files/7032993454.pdf
    • https://cdn.shopify.com/s/files/1/0432/5962/5627/files/rosutobetoxima.pdf
    • https://cdn.shopify.com/s/files/1/0437/8476/5602/files/adenocarcinoma_gastrico_difuso.pdf
    • https://cdn.shopify.com/s/files/1/0427/8249/0791/files/54653429085.pdf
    • https://cdn.shopify.com/s/files/1/0430/6917/8017/files/silmarillion_ainulindale.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_off00006521.bin
e9edd7de68bc6abc01bebbb7d837d272df90f3ec8eedc5e8f609b9a3184ec3e9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6521 5192 bytes
font_01_sfnt_off000076b9.bin
b9fca7073c89ca9ae136fc626accce10603e2d1a753a11076a00319a107c66a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x76B9 14864 bytes