Malicious PDF — malware analysis report

Static analysis result for SHA-256 41cb53c7f3a25015…

MALICIOUS

PDF

73.1 KB Created: 2021-09-18 05:37:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7f35e69a66c1c15806efc17924f8ebf3 SHA-1: d0b88e55a0c737b7df46ccd36d34eb31741543a9 SHA-256: 41cb53c7f3a25015524ddd577166ada0b7f31873f8e4f615587e6f65a8097fc0
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm pointing to multiple domains, with several identified as compromised CMS upload storage or disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, and the document body was truncated and unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://driftwoodcc.com/userfiles/files/21449529256.pdf In PDF document text
    • http://venusland.vn/app/webroot/img/files/86704533255.pdfIn PDF document text
    • https://nk-sostanj.si/files/file/33067898304.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/4220893171.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///37594004649.pdfIn PDF document text
    • http://someteme.com/archivos/_20210918000617.pdfIn PDF document text
    • https://resortweeks.pro/userfiles/file/83621978530.pdfIn PDF document text
    • http://www.oe.com.tw/ezadmin/ckfinder/userfiles/files/56558213707.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/68518988447.pdfIn PDF document text
    • http://bloodfaces.de/attachment/file/19287728748.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/26837193227.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/99662226898.pdfIn PDF document text
    • http://kes.org/upload/editor/files/44364420291.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140bd58c66f4---55566906682.pdfIn PDF document text
    • https://adminico.nl/userfiles/file/29575484383.pdfIn PDF document text
    • http://fs-select.com/images/blog/file/99428653492.pdfIn PDF document text
    • http://antoniolescio.net/userfiles/files/rolijodetitafaxumev.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/3c625bccb32c81c3c0c7cdd48b63cdaa/nemifoponuxisajabaruku.pdfIn PDF document text
    • http://2018.letnifestiwal.pl/ckfinder/userfiles/files/roxetovizamosewifos.pdfIn PDF document text
    • https://equinox-e.com/upload/files/lozarixekedisis.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/86678122506.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/da67eebdc76ebea1fa0f6eac469de385/dewonamuruxozosanetemeluv.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/mefabufal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=most+deadly+snake+in+australiaPDF link annotation
    • 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_off0000bc39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC39 16676 bytes
SHA-256: c3579ad82f723c6edb8e2917973b9ca29657ad8279105e1305177ba4ec5c340d
font_01_sfnt_off0000e67f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67F 10540 bytes
SHA-256: 5436cbf673369ba776c30a7733f882217b7261c3eedf4614c7f3aed083a79341
font_02_sfnt_off0000feb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1