Malicious PDF — malware analysis report

Static analysis result for SHA-256 263c99759fa62a5f…

MALICIOUS

PDF

80.4 KB Created: 2021-09-17 18:28:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7a7099e0defa3a342daaf3236707866 SHA-1: 32677a6073e41000adc31a73697501014bf35f94 SHA-256: 263c99759fa62a5f212ef2423121d20a671cc8956da18d777f0680f11dd5de14
154 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of multiple external URIs and link farms indicates an attempt to redirect users to potentially harmful sites, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5466

Heuristics 5

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://vaynhanh365.net/contents/files/46911380902.pdf
    • http://china-baby-clothes.com/d/files/nonulijimodalo.pdf
    • http://dealershop.es/userfiles/file/23863552319.pdf
    • http://chpcentre.com/files/file/5506379984.pdf
    • http://noithatdangcap.vn/app/webroot/uploads/files/wokosojegavago.pdf
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/pgcp896jd168c6oo5k84jabhf0/fozixipagadoju.pdf
    • http://biomehl.com/images/content/files/5662950483.pdf
    • https://farmaciasacoor.com/site/upload/file/68212311713.pdf
    • http://asfalon.com/__files/file/bojizabapikusi.pdf
    • http://www.findvoters.com/userfiles/file/84331964011.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/bbdf4f8133be76d6a6ac2170d9111df8/72198984171.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/d2bg49ctt2gv2pq2dlpkud7510/biwajanigi.pdf
    • http://bibliotekaludwin.pl/img/upload/files/97247447750.pdf
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/66646716966.pdf
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/reramexufukanubufefin.pdf
    • http://vin-baietii.ro/ckfinder/userfiles/files/9256588200.pdf
    • http://kor-ra.ru/UserFiles/file/zidufuwetusudiz.pdf
    • https://futurefacesmiami.com/uploads/file/24991314809.pdf
    • http://abwrichmond.com/uploads/files/76861393012.pdf
    • http://dalaichau.com/files/nesemoxilagaj.pdf
    • http://sonsuadogo.org/Images_upload/files/50958437998.pdf
    • https://atavio.ru/files/file/kenujeke.pdf
    • http://rpsbchamber.org/editorData/file/10837177396.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/161380d520b992---pipefudulesewosexafe.pdf
    • http://klpa.net/userData/board/file/45592919483.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/pgc25dtvucm4ea4qr5c1sonrkk/xofomosoxezatiwizuba.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=oceanhorn+apk+full
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7f0.bin
1c13afb4589ceec5f44695f866793b306c3beaabcf1901504256e4cfff5fa864
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F0 19444 bytes
font_01_sfnt_off00011a52.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A52 16792 bytes