Malicious PDF — malware analysis report

Static analysis result for SHA-256 53430d537a91c5b0…

MALICIOUS

PDF

80.6 KB Created: 2021-09-21 17:36:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 17a2d11408af99315973964e5ffdac47 SHA-1: 33e3cb316fcbf3b8e9c98c16df7c44ffb1607f40 SHA-256: 53430d537a91c5b04e0a986b0456650f9c4bd970f7beb56ed75a1526a577a435
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to disposable domains or compromised CMS upload storage, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

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://pistant.ru/uplcv?utm_term=nasal+sinuses+function PDF link annotation
    • http://dryoucosmeceutical.com/userfiles/files/saneriwitulazi.pdfIn PDF document text
    • https://tcremich.lu/files/files/63877533382.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/pizinazoki.pdfIn PDF document text
    • http://crmloccitanecr.com/campannas/file/foxik.pdfIn PDF document text
    • http://gucaoyun.com/uploads/file/090053306334.pdfIn PDF document text
    • https://zoldlaptop.hu/ckfinder/userfiles/files/dofawomip.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/88263823106.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/161419123a782d---80462041757.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/zifiginipaserilanonido.pdfIn PDF document text
    • https://notarbrazda.cz/userfiles/file/In PDF document text
    • https://oxi-dental.ro/imagini_ws/vazuxajug.pdfIn PDF document text
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tamowi.pdfIn PDF document text
    • https://khogiaydantuonghanquoc.com/images/news/file/68991807674.pdfIn PDF document text
    • https://atrax.hr/files/32064647282.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139c5a128e27---34735748248.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/dimolafixu.pdfIn PDF document text
    • http://palenice.net/obrazky_clanky/file/nibavujozez.pdfIn PDF document text
    • http://honyi.tw/ckfinder/userfiles/file/gofudagatabu.pdfIn PDF document text
    • http://15881588.com/ckupload/files/xumiv.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/161463b7c960c6---61971340126.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/38176552282.pdfIn PDF document text
    • https://suacuacuontoanphat.com/upload/files/jedepijawokowumusowov.pdfIn PDF document text
    • http://serting.eu/userfiles/files/weverovemopizojur.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/63194029659.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_off0000d852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD852 17448 bytes
SHA-256: 20afee95294ff346390e0558eafb5983d223a65fd520f6f792074faaf7f734ec
font_01_sfnt_off00010578.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10578 10308 bytes
SHA-256: 0145c4076ec947558b0917e290303b4535078f62392a3d7fa4e2b30453149b17
font_02_sfnt_off00011cda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1