Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca43796f4a096f22…

MALICIOUS

PDF

80.0 KB Created: 2021-09-10 05:26:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1f56898e83199255e08a2b52b517a8c3 SHA-1: 133340231ae904ab84fd98f97f096bbf68bdb981 SHA-256: ca43796f4a096f22440cfe8aaaa8585e1402786901d99a4281c7a01734dff382
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall heuristic firings strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 https://archism.ru/uplcv?utm_term=otg+support+apk+download PDF link annotation
    • http://uro-medical.pl/zdjecia/fotki/file/77550816764.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/94948678489.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/robuzubodelabazej.pdfIn PDF document text
    • http://mislenyiallatorvos.hu/userfiles/file/sipupejatuvororidom.pdfIn PDF document text
    • http://ridendo.cz/files/file/52725997336.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/pizixojurinorumujejisaka.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/161309627935f2---gedanokuvemolexu.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/lowusemug.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/wupimiradetumikizotom.pdfIn PDF document text
    • https://beaszemin.com/files/54300657664.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/eeqdvhln9eqr5hf7fl1av9nig1/68723739348.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/498ec0b4efcc07b0690f691333c075c4/31524881093.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/kapomejolelosovivinitun.pdfIn PDF document text
    • http://azizolace.cz/images/file/tufedukuzozolexafafujixo.pdfIn PDF document text
    • https://vegas-shop.net/uploads/files/jaletupuxefigaxipiwulub.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/dolerabidajarovere.pdfIn PDF document text
    • http://workontext.ru/media/file/11564160598.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/81139798648.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/nujukevuxilazopazonaf.pdfIn PDF document text
    • https://naveenent.com/administrator/imagetemp/file/zerujuzuximozojiguvane.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/cff1ee4c336f1c9e315a0ffd0847cebd/15883758081.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD632 10648 bytes
SHA-256: 32a0f5e4d02de017b218a378bc4de11364a8637800758b790ecc5c6ae3f6f2ed
font_01_sfnt_off0000ee96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE96 17088 bytes
SHA-256: c73be036ef0935f9da1b314db61d704729d82187e99894bbbdc911f5949738eb
font_02_sfnt_off00011aaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1