Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c86859f0100546…

MALICIOUS

PDF

80.0 KB Created: 2021-08-22 02:34:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 096f3f2a74bc22a62b57b3d118cf002a SHA-1: 937b5cc6866d29980bf6ff462c7e29f47907c9d9 SHA-256: a4c86859f0100546fc0d409175b43e3d7f207ddd27617e3273f4b9ad331cd4c2
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document contains a large number of links, many of which point to compromised WordPress sites or disposable domains. The ML classifier strongly indicated maliciousness. The primary function appears to be acting as a link farm, likely for SEO poisoning or to redirect users to malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/tasubimub.pdf
    • http://sugarfree-gelato.com/upload/file/90371076900.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607183b5ddc72---bibizijamitigotajatilotu.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/4qo8dpftm8mk8fe62og9j7cshk/samorakukejimogopuzopufu.pdf
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/54455479355.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c758c9dffc---busuv.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/55d1df8506375188ba5f67d1ce19b1fd/72098700755.pdf
    • http://beliangka.com/contents//files/podofuzozekitazilebeso.pdf
    • http://www.anjhimayath.com/upload/file/jokizugobez.pdf
    • http://ikkosushi.com/uploads/files/danefateralora.pdf
    • http://shriadinathbank.com/uploads/28141549661.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c84499ae95---66368514436.pdf
    • http://statsale.com/data/upload/ck/files/wilafimuseferomeki.pdf
    • https://foundryindia.org/userfiles/file/57165037695.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/8218e4990cf4831e8fb956e67cc5a9e4/kovefogez.pdf
    • https://soudurelausiere.ca/upload/editor/file/rezufujapokadufototasav.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a2cb74efe86---zosurosotu.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/0c40699072a95a11430511bf8f6b7bf8/58014009408.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/2jbufvipdjk8k4ul25eme465ug/tiwonulagoterubowiridolug.pdf
    • http://a-mega.ua/images/uploads/file/96103626512.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c4df9c819fd---rafifepupuwot.pdf
    • http://fontanarosaserigrafia.it/userfiles/file/roraxaturidejenori.pdf
    • http://sl-light.ru/design/img/upload/file/61362757871.pdf
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/df1b72c63a160745a917c1be38b3f78a/bovujiwemiwupufuvuvutelan.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=kalai+vanakkam+images+tamil+hd
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d503.bin
841c99b64dafab3099776a6709d94d4e2fb4d37cf2d88d9621fd604ddb115460
pdf-font-stream PDF embedded font (sfnt) at offset 0xD503 10624 bytes
font_01_sfnt_off0000ece5.bin
311a1d9dcdba5948723030fa62b7bd5e97ed334ca220dd4e176773d8d05d421e
pdf-font-stream PDF embedded font (sfnt) at offset 0xECE5 16572 bytes
font_02_sfnt_off000116f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x116F7 16792 bytes