Malicious PDF — malware analysis report

Static analysis result for SHA-256 516c9d73f89f720b…

MALICIOUS

PDF

113.4 KB Created: 2021-06-26 16:08:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 83e70015b57f967d19f4298b4b3d02eb SHA-1: 1d3ddb22be6376c898be6338713f9fb0ab89f354 SHA-256: 516c9d73f89f720b5f7c57fb4c671d7f28172ee3d0ea38352a909580da334943
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the presence of link farms and compromised CMS uploads, suggesting the document is designed to redirect users to malicious sites or download further payloads. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9746

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://szpital-sulecin.pl/images/fckfiles/file/gulenopusosap.pdf
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/fuletozawebigavosuwix.pdf
    • https://gulyaskantin.hu/uploads/frontend/files/88085158688.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/4f36c5bc00c4bea0411adb0ff81b0f80/55959696836.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/4c140f589b8d29f75504fad2204042d9/15262191673.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607556dabe105---perawilalumetupozon.pdf
    • https://apz-arte.com/ckfinder/userfiles/files/wikugixebevaf.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb65db0681---70842126798.pdf
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/56afdd5341581e2411965207357a48d5/3862304204.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/iglqqvi0lvoub5jjelggq92tbl/52593514397.pdf
    • http://fiumevivo.it/userfiles/files/kugusoposov.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada42580067---75849865561.pdf
    • http://taketty.xyz/js/ckfinder/userfiles/files/sogiwirox.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/hodu3sqrcjo6tp69cuofjlvui7/9276842532.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e26f2e0ba8---bawiluriwolajex.pdf
    • https://botorka.ro/userfiles/file/60636804588.pdf
    • https://africanresearchcenter.com/userfiles/file/guzikafanolasegopajit.pdf
    • http://matstravel.ru/userfiles/file/32326132572.pdf
    • http://bafiti.com/sklep/userfiles/file/95762476935.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/ej0ipbu829tg6rafrkq4krbvac/98692042963.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb15fa1c3f---39200913274.pdf
    • https://aslimitada.com/userfiles/file/bulapuzejekejawotemuzezo.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd89432c6f---jumexilidobosososak.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=enable+meaning+in+english
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00014a96.bin
690feac530d01d95f8f93f8494a3f35f2e9ae55f5bd9ebdeea5eee0bf3f4ddc6
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x14A96 21872 bytes
font_00_sfnt_off00010223.bin
b7970e6202ee17805633cc8cc81c9d5e1f90a3cf075d03247f28d0ef6797bb13
pdf-font-stream PDF embedded font (sfnt) at offset 0x10223 30880 bytes
font_02_sfnt_off00017268.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17268 16792 bytes
font_03_sfnt_off00018a75.bin
8cb5f6b7b7fd217075732eb1e2d8c06377cf6a2cf70fb1d415d7c0a01c551528
pdf-font-stream PDF embedded font (sfnt) at offset 0x18A75 5624 bytes
font_04_sfnt_off00019e6f.bin
ac67ccaf737919d45ea7ee321487c55594eb84891136884dc12b6cbd251f54af
pdf-font-stream PDF embedded font (sfnt) at offset 0x19E6F 10360 bytes